Research Highlights

  • The Great Spin Swap
    September 18, 2013
    PI(s): Ana Maria Rey, Deborah Jin, Jun Ye
    Topic(s): Atomic & Molecular Physics

    Research associate Bo Yan and his colleagues recently observed spin exchanges in ultracold potassium-rubidium (KRb) molecules inside an optical lattice (a crystal of light formed by interacting laser beams). In solid materials, such spin exchanges are the building blocks of advanced materials and exotic behavior.

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  • The Magnificent Quantum Laboratory
    August 08, 2013
    PI(s): Ana Maria Rey, Jun Ye
    Topic(s): Quantum Information Science & Technology

    Because quantum mechanics is crucial to understanding the behavior of everything in the Universe, one can understand key elements of the behavior of a neutron star by investigating the behavior of an atomic system in the laboratory. This is the promise of the new quantum simulator in the Ye labs. It is a fully controllable quantum system that is being used as a laboratory to study the behavior of other less controllable and more poorly understood quantum systems.

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  • Persistence of Memory
    August 02, 2013
    PI(s): Phil Armitage
    Topic(s): Astrophysics

    What sets the stage for planet formation? To search for answers to this question, research associate Jake Simon and his colleagues are performing a series of high-level computer simulations of the outer disks around young stars such as TW Hydrae, shown here. Simon’s daunting task is being facilitated with new information that has just started to come in from the Atacama Large Millimeter/submillimeter Array (ALMA) observatory in Chile.

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  • Life in the Fast Lane
    July 26, 2013
    PI(s): Andreas Becker, Henry Kapteyn, Margaret Murnane
    Topic(s): Atomic & Molecular Physics

    Many people are familiar with the beautiful harmonies created when two sound waves interfere with each other, producing a periodic and repeating pattern that is music to our ears. In a similar fashion, two interfering x-ray waves may soon make it possible to create the fastest possible strobe light ever made. This strobe light will blink fast enough to allow researchers to study the nuclei of atoms and other incredibly tiny structures. The new strobe light is actually very fast coherent laser-like radiation created by the interference of high-energy x-ray waves.

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  • Quantum Legoland
    July 01, 2013
    PI(s): Murray Holland
    Topic(s): Atomic & Molecular Physics

    The quantum world is not quite as mysterious as we thought it was. It turns out that there are highways into understanding this strange universe. And, graduate students Minghui Xu and David Tieri with Fellow Murray Holland have just discovered one such superhighway that has been around since the 1950s. Traveling along this superhighway has made it possible to understand the quantum behavior of hundreds of atoms inside every laser used in JILA, including the superradiant laser in the Thompson lab that works entirely differently from all the others.

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  • Not All who Wander are Lost
    June 25, 2013
    PI(s): Henry Kapteyn, Margaret Murnane
    Topic(s): Nanoscience

    When research associate Wei Xiong and graduate student Dan Hickstein studied quantum dots by shining laser light on them in the gas phase, they got some surprising results. The tiny chunks of material responded differently to series of two laser pulses — depending on their size. Scientists already knew that most of their quantum dots would end up with at least part of an electron wandering around outside of them for some period of time. However, Xiong and his colleagues showed that the electrons from the smallest quantum dots traveled the farthest away.

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  • Trapper Marmot and the Stone Cold Molecules
    April 01, 2013
    PI(s): Jun Ye
    Topic(s): Atomic & Molecular Physics

    The Ye group has opened a new gateway into the relatively unexplored terrain of ultracold chemistry. Research associate Matt Hummon, graduate students Mark Yeo and Alejandra Collopy, newly minted Ph.D. Ben Stuhl, Fellow Jun Ye, and a visiting colleague Yong Xia (East China Normal University) have built a magneto-optical trap (MOT) for yttrium oxide (YO) molecules. The two-dimensional MOT uses three lasers and carefully adjusted magnetic fields to partially confine, concentrate, and cool the YO molecules to transverse temperatures of ~2 mK. It is the first device of its kind to successfully laser cool and confine ordinary molecules found in nature.

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  • The Transporter
    March 15, 2013
    PI(s): Konrad Lehnert
    Topic(s): Quantum Information Science & Technology

    The Lehnert group has come up with a clever way to transport and store quantum information. Research associate Tauno Palomaki, graduate student Jennifer Harlow, NIST colleagues Jon Teufel and Ray Simmonds, and Fellow Konrad Lehnert have encoded a quantum state onto an electric circuit and figured out how to transport the information from the circuit into a tiny mechanical drum, where is stored. Palomaki and his colleagues can retrieve the information by reconverting it into an electrical signal.

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  • Alien Atmospheric Chemistry
    March 13, 2013
    PI(s): Jeffrey Linsky
    Topic(s): Astrophysics

    Astrophysicist Fellow Jeff Linsky and his colleagues from CU’s Center for Astrophysics and Space Astronomy have come up with a neat strategy for helping to determine whether an exoplanet’s atmosphere contains evidence of Earth-like life. The first step is to see whether an exoplanet’s atmosphere contains oxygen (O2), ozone (O3), or other molecules that could have been produced by Earth-like organisms such as the plants that produce O2. Next, Linsky and his collaborators propose analyzing spectral lines from the host star’s light to determine if the same molecules could exist in the atmosphere without life.

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  • Countdown to Launch
    February 15, 2013
    PI(s): Mitch Begelman
    Topic(s): Astrophysics

    Fellow Mitch Begelman and colleague Marek Sikora of the Polish Academy of Sciences have proposed a solution for the long-standing puzzle of what causes black holes to launch powerful jets. Jets are extremely energetic material (plasma) traveling at very close to the speed of light and spanning distances of thousands to hundreds of thousands of light years.

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  • Position Wanted
    February 14, 2013
    PI(s): Cindy Regal
    Topic(s): Precision Measurement, Quantum Information Science & Technology

    Researchers in the Regal group have gotten so good at using laser light to track the exact position of a tiny drum that they have been able to observe a limit imposed by the laws of quantum mechanics. In a recent experiment, research associate Tom Purdy, graduate student Robert Peterson, and Fellow Cindy Regal were able to measure the motion of the drum by sending light back and forth through it many times. During the measurement, however, 100 million photons from the laser beam struck the drum at random and made it vibrate. This extra vibration obscured the motion of the drum at exactly the level of precision predicted by the laws of quantum mechanics.

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  • Model Behavior
    February 13, 2013
    PI(s): Ana Maria Rey
    Topic(s): Atomic & Molecular Physics

    Ana Maria Rey’s group is devising new theoretical methods to help experimentalists use ultracold atoms, ions, and molecules to model quantum magnetism in solids. Research associate Kaden Hazzard, former research associate Salvatore Manmana, newly minted Ph.D. Michael Foss-Feig, and Fellow Rey are working on developing new tools to understand these models, which describe both solids and ultracold particles. The theorists are collaborating with three experimental teams at JILA and the National Institute of Standards and Technology (NIST).

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  • Physicists on the Verge of Mean-Field Breakdown
    February 05, 2013
    PI(s): Ana Maria Rey
    Topic(s): Atomic & Molecular Physics

    When experimental physicists at Penn State were unable to observe some of the predicted behaviors of ultracold rubidium (Rb) atoms expanding inside a two-dimensional crystal of light, they turned to their theorist colleagues at the City University of New York and JILA for an explanation. Graduate student Shuming Li and Fellow Ana Maria Rey were happy to oblige.

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  • The Pathfinder
    January 22, 2013
    PI(s): Steven Cundiff
    Topic(s): Atomic & Molecular Physics

    The Cundiff group has taken an important step forward in the study of the quantum world. It has come up with an experimental technique to measure key parameters needed to solve the Schrödinger equation. The amazing Schrödinger equation describes the time-dependent evolution of quantum states in a physical system such as the group’s hot gas of potassium atoms (K). But, for the equation to work, someone has to figure out a key part of the equation known as the Hamiltonian.

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  • Going for the Gold
    January 07, 2013
    PI(s): Thomas Perkins
    Topic(s):

    Gold glitters because it is highly reflective, a quality once considered important for precision measurements made with gold-coated probes in atomic force microscopy (AFM). In reality, the usual gold coating on AFM probes is a major cause of force instability and measurement imprecision, according to research done by the Perkins group.

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  • The Big Chill
    December 19, 2012
    PI(s): John Bohn, Jun Ye
    Topic(s): Atomic & Molecular Physics

    The Ye and Bohn groups have made a major advance in the quest to prepare “real-world” molecules at ultracold temperatures. As recently reported in Nature, graduate students Ben Stuhl and Mark Yeo, research associate Matt Hummon, and Fellow Jun Ye succeeded in cooling hydroxyl radical molecules (*OH) down to temperatures of no more than five thousandths of a degree above absolute zero (5mK).

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  • The Heart of Darkness
    December 18, 2012
    PI(s): James Thompson
    Topic(s): Laser Physics

    When the Thompson group first demonstrated its innovative “superradiant” laser the team noticed that sometimes the amount of light emitted by the laser would fluctuate up and down.  The researchers wondered what was causing these fluctuations. They were especially concerned that whatever it was could also be a problem in future lasers based on the same principles.

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  • The Amazing Plasmon
    December 12, 2012
    PI(s): David Nesbitt
    Topic(s): Nanoscience

    The Nesbitt group has figured out the central role of “plasmon resonances” in light-induced emission of electrons from gold or silver nanoparticles. Plasmons are rapid-fire electron oscillations of freely moving (conduction) electrons in metals. They are caused by light of just the “right frequency.”

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  • Refueling the Future - with Carbon Dioxide
    December 07, 2012
    PI(s): J. Mathias Weber
    Topic(s): Chemical Physics

    Graduate student Ben Knurr and Fellow Mathias Weber have added new insight into a catalytic reaction based on a single gold atom with an extra electron that transfers this electron into carbon dioxide molecules (CO2). This reaction could be an important first step future industrial processes converting waste CO2 back into chemical fuels. As such, it could play a key role in a future carbon-neutral fuel cycle.

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  • The Most Stable Clock in the World
    December 05, 2012
    PI(s): Jun Ye
    Topic(s): Precision Measurement

    The world’s most stable optical atomic clock resides in the Ye lab in the basement of JILA’s S-Wing. The strontium-(Sr-)lattice clock is so stable that its frequency measurements don’t vary by more than 1 part in 100 quadrillion (1 x 10-17) over a time period of 1000 seconds, or 17 minutes.

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  • The Entanglement Tango
    December 05, 2012
    PI(s): Ana Maria Rey, James Thompson
    Topic(s): Atomic & Molecular Physics

    Most scientists think it is really hard to correlate, or entangle, the quantum spin states of many particles in an ultracold gas of fermions. Fermions are particles like electrons (and some atoms and molecules) whose quantum spin states prevent them from occupying the same lowest-energy state and forming a Bose-Einstein condensate. Entanglement means that two or more particles interact and retain a connection. Once particles are entangled, if something changes in one of them, all linked partners respond.

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  • Everything's Cool with Atom
    November 29, 2012
    PI(s): Cindy Regal
    Topic(s): Atomic & Molecular Physics

    The Regal group recently completed a nifty feat that had never been done before: The researchers grabbed onto a single trapped rubidium atom (87Rb) and placed it in its quantum ground state. This experiment has identified an important source of cold atoms that can be arbitrarily manipulated for investigations of quantum simulations and quantum logic gates in future high-speed computers.

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  • Close Encounters with the Contact
    October 22, 2012
    PI(s): Deborah Jin, Eric Cornell
    Topic(s): Atomic & Molecular Physics

    The Jin and Cornell groups have discovered irrefutable evidence for the contact. The contact appears in ultracold gases under conditions when the atoms are close “contact” in a Bose-Einstein condensate, or BEC.  Like pressure, volume, and temperature, the contact is an important property of ultracold ensembles of atoms.  The contact is particularly important when the atoms interact with each other, since the contact tells you how likely it is that an atom in the ensemble is having a close encounter with another atom.

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  • Sizzling Vibrations
    October 18, 2012
    PI(s): Andreas Becker
    Topic(s): Atomic & Molecular Physics

    Former research associate Antonio Picón, research associate Agnieszka Jaron-Becker, and Fellow Andreas Becker have discovered a way to make the hydrogen molecular ion (H2+) fall apart into its constituent atoms without exciting or ionizing the electron. This startling finding was a big surprise for the researchers, who recently figured out how to do something that conventional wisdom said was difficult, if not downright impossible.

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  • A More Perfectly Understood Union
    October 18, 2012
    PI(s): Other
    Topic(s): Astrophysics

    Research associate Bruno Giacomazzo recently studied the effects of magnetic fields and matter on the likelihood that the merger of two black holes will produce jets of light of different frequencies ranging from radio waves to X-rays. If such signals are generated, it may be possible to detect them with ground- or space-based observatories. Their detection would help astronomers identify and study the unions of supermassive black holes that occur after galaxies collide. Supermassive black holes are found at the centers of most galaxies in the Universe.

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  • Messages from the Abyss
    October 10, 2012
    PI(s): Rosalba Perna
    Topic(s): Astrophysics

    Many neutron stars are surrounded by accretion disks. The disks are often made up of matter pulled in by the neutron star’s gravity from a companion star in a binary system. Over time, the neutron stars can swallow so much additional material that they collapse into black holes.

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  • Scratching the Surface
    October 08, 2012
    PI(s): Deborah Jin
    Topic(s): Atomic & Molecular Physics

    Members of the Jin group found a way to measure for the first time the a type of abstract “surface” in a gas of ultracold atoms that had been predicted in 1926 but not previously observed. Jin and her colleagues are leading researchers in the field of ultracold Fermi gases made up of thousands to millions of fermions.

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  • New Silicon Cavity Silences Laser Noise
    September 12, 2012
    PI(s): Jun Ye
    Topic(s): Precision Measurement

    Researchers from a German national laboratory, the Physikalisch-Technische Bundesanstalt (PTB) have collaborated with Fellow Jun Ye, Visiting Fellow Lisheng Chen (Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences), and graduate student Mike Martin to come up with a clever approach to reducing heat-related “noise” in interferometers. 

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  • The Spider's Secret
    August 22, 2012
    PI(s): Henry Kapteyn, Margaret Murnane
    Topic(s): Atomic & Molecular Physics

    Graduate student Dan Hickstein (Kapteyn/Murnane group) recently investigated the behavior of electrons ripped from atoms and molecules by intense infrared laser pulses. He and his colleagues collected the liberated electrons onto a detector where they formed intricate patterns that looked a lot like giant spiders. 

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  • Way Faster than a Speeding Bullet
    June 18, 2012
    PI(s): David Nesbitt
    Topic(s): Chemical Physics

    The interface between a gas and a solid is a remarkable environment for new investigations. Lots of fascinating chemistry takes place there, including catalysis. Catalysis is acceleration of a chemical reaction that is caused by an element like platinum that remains unchanged by a chemical reaction. For instance platinum catalyzes the transformation of carbon monoxide (CO) into carbon dioxide (CO2) in automobile catalytic converters. A better understanding of catalysis could improve the efficiency of manufacturing important chemicals as well as expanding our fundamental knowledge of chemistry.

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  • X-Ray Visionaries
    June 07, 2012
    PI(s): Henry Kapteyn, Margaret Murnane
    Topic(s): Atomic & Molecular Physics

    The Kapteyn/Murnane group had the idea that it might be possible to produce bright, laser-like beams of x-rays using an ultrafast laser that fits on a small optics table. It was one of those “it probably can’t be done, but we have to try” moments that motivated them to put together a team that includes the Becker theory group, and 16 collaborators in New York, Austria, and Spain. The lead scientist on this effort, Dr. Tenio Popmintchev, was most concerned about the possibility of an explosion, because to generate x-rays at high photon energies, the laser needed to be focused into a fiber containing high-density helium gas at pressures as high as 80 atmospheres. Eighty atmospheres is 80 times the normal air pressure at sea level.

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  • RNA Folding: The Rest of the Story
    June 06, 2012
    PI(s): David Nesbitt
    Topic(s): Biophysics

    The Nesbitt group has been investigating RNA folding since the early 2000s. The group’s goal has been to gain a detailed understanding of the relationship between structure and function in this important biomolecule. One challenge has been figuring out how unfolded RNA molecules assume the proper three-dimensional (3D) shape to perform their biological activities. To accomplish this, the researchers have shown how biologically active RNA is able to neutralize negative charges that end up in close proximity to each other after folding into a 3D structure.

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  • New Flavors of Quantum Magnetism
    May 24, 2012
    PI(s): Ana Maria Rey
    Topic(s): Quantum Information Science & Technology

    News Flash!  The Rey group has discovered another good reason for using alkaline-earth atoms, such as strontium (Sr) or Ytterbium (Yb), in experimental quantum simulators. Quantum simulators are systems that mimic interesting materials or mathematical models in a very controlled way. The new reason for using alkaline earth atoms in such systems comes from the fact that their nuclei come in as many as 10 different magnetic flavors, i.e., their spins can be in 10 different quantum states.

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  • New Beginnings: JILA welcomes the Janus supercomputer
    May 09, 2012
    PI(s):
    Topic(s): Other

    In Roman mythology, Janus is the god of beginnings and transitions, of doors and bridges, as well as endings and time.  The aptly named Janus supercomputer at CU is bringing new opportunities in high-performance research computing to JILA. Since the fall of 2010, JILA groups directed by Andreas Becker, Mitch Begelman, Chris Greene, Ana Maria Rey, and Juri Toomre have used more than 25 million CPU hours on Janus for research in astrophysics and AMO physics.

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  • Diary of a Binge Eater
    May 03, 2012
    PI(s): Mitch Begelman
    Topic(s): Astrophysics

    Fellow Mitch Begelman and his colleagues came up with the idea of quasistars to explain the origin of the supermassive black holes found at the center of most galaxies. According to Begelman, quasistars formed when massive amounts of gas were funneled into the center of protogalaxies. This prodigious amount of gas collapsed directly into black holes without forming stars.

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  • Molding a Star System over 50 Million Years
    April 20, 2012
    PI(s): Phil Armitage
    Topic(s): Astrophysics

    Giant planets form inside a disk of gas and dust orbiting a new star. At first, gravitational interactions between the disk and the planets will keep planetary orbits circular, according to Fellow Phil Armitage. But, once the disk begins to disperse, things get very interesting.

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  • The Laser with Perfect Pitch
    April 04, 2012
    PI(s): James Thompson
    Topic(s): Laser Physics

    The Thompson group, with theory help from the Holland group, recently demonstrated a superradiant laser that escapes the “echo chamber” problem that limits the best lasers. To understand this problem, imagine an opera singer practicing in an echo chamber. The singer hears his own voice echo from the walls of the room. He constantly adjusts his pitch to match that of his echo from some time before. But, if the walls of the room vibrate, then the singer’s echo will be shifted in pitch after bouncing off of the walls. As a result, if the singer initially started singing an A, he may eventually end up singing a B flat, or a G sharp, or any other random note — spoiling a perfectly good night at the opera.

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  • Secrets of a Celestial Accelerator
    March 20, 2012
    PI(s): Mitch Begelman
    Topic(s): Astrophysics

    On Earth, people use enormous linear accelerators and synchrotrons for such purposes as high-energy physics experiments, chemical composition analysis, and drug research. Linear accelerators ramp up the speeds of electrons and other charged subatomic particles close to the speed of light. Synchrotrons also accelerate charged particles (in a circular track) that, when deflected through magnetic fields, create extremely bright high-energy light. 

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  • The Secret Life of Magnets
    March 15, 2012
    PI(s): Henry Kapteyn, Margaret Murnane
    Topic(s): Laser Physics

    The Kapteyn/Murnane group and scientists from NIST Boulder and Germany have figured out how the interaction of an ultrafast laser with a metal alloy of iron and nickel destroys the metal’s magnetism. In a recent experiment, the researchers were able to observe how individual bits of quantum mechanical magnetization known as “spin” behaved after the metal was heated with the laser.

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  • Variation on an Infinity of Triangles
    February 21, 2012
    PI(s): Chris Greene
    Topic(s): Atomic & Molecular Physics

    The Greene group has just discovered some weird quantum states of ultracold fermions that are also dipoles. Dipoles are particles with small positively and negatively charged ends. Atoms (or molecules) that are fermions cannot occupy the same quantum state — unlike the neighborly bosons that readily occupy the same state and form Bose-Einstein condensates at ultracold temperatures. The new theoretical study was interesting because it explored what would happen to dipolar fermions under the same conditions that cause dipolar bosons to form infinitely many three-atom molecules even though no two bosons ever form a molecule under these conditions!

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  • The Indomitable Ruler of Light
    February 02, 2012
    PI(s): Jun Ye
    Topic(s): Laser Physics

    The Ye group has created the world’s first “ruler of light” in the extreme ultraviolet (XUV). The new ruler is also known more formally as the XUV frequency comb. The comb consists of hundreds of equally spaced “colors” that function in precision measurement like the tics on an ordinary ruler. The amazing thing about this ruler is that XUV colors have such short wavelengths they aren’t even visible to the human eye. The wavelengths of the XUV colors range from about 120 nm to about 50 nm — far shorter than the shortest visible light at 400 nm. “Seeing” the colors in the XUV ruler requires special instruments in the laboratory. With these instruments, the new ruler is opening up whole new vistas of research.

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  • No free lunch for entangled particles
    January 26, 2012
    PI(s): Ana Maria Rey
    Topic(s): Atomic & Molecular Physics

    Incredibly sensitive measurements can be made using particles that are correlated in a special way (called entanglement.)  Entanglement is one of the spooky properties of quantum mechanics – two particles interact and retain a connection, even if separated by huge distances.  If you do something to one of the particles, its linked partners will also respond.

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  • Schrödinger Cats Light the Way
    January 13, 2012
    PI(s): Steven Cundiff
    Topic(s): Nanoscience

    We can get valuable information about a material by studying how it responds to light.  But up to now, researchers have been forced to ignore how some of light’s stranger quantum behavior, such as being in a superposition of one or more intensity states, affects these measurements.  New research from the Cundiff group (with newly minted PhD Ryan Smith and graduate student Andy Hunter) has shown that it is possible to back-calculate how a semiconductor responds to light’s quantum features even though we can’t directly create light with those features.

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  • Simulating a Starquake
    December 28, 2011
    PI(s): Rosalba Perna
    Topic(s): Astrophysics

    Some stars die dramatically – the light from the supernova explosion of a distant massive star can outshine an entire galaxy. But this event isn’t the endgame for the star — the dense remnants of some of these explosions (called neutron stars) can spit out light rays over thousands of years. 

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  • Quantum Body Swapping
    October 28, 2011
    PI(s): Andreas Becker
    Topic(s): Atomic & Molecular Physics

    Theorists Norio Takemoto (now at the Weizmann Institute of Science) and Fellow Andreas Becker figured that something was amiss when they first analyzed the details of what occurs when an ultrafast laser dislodges an electron from a “simple” molecular ion, H2+. Since H2has already lost one of its electrons, its two protons only have one electron left to play with.  How hard would it be to “see” what happened to this electron in a strong laser field? After all, a widely accepted theory said that a strong laser field would make it easier for the lone electron to escape when the ion was stretched apart (as opposed to contracted). 

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  • Cross-Cultural Spectroscopy
    October 19, 2011
    PI(s): Ralph Jimenez
    Topic(s): Biophysics

    Graduate student Jennifer Lubbeck (Jimenez Group) spent the summer of 2011 doing research in the Molecular Spectroscopy Laboratory at the RIKEN Institute in Wako, Japan (near Tokyo). Her host's group included 16 postdocs and four graduate students. The group was under the direction of Chief Scientist Tahei Tahara. However, Lubbeck actually worked directly with just five other young scientists under the supervision of Professor Kunihiko Ishi (Ishi-san).

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  • Chemistry in the Cosmos
    October 19, 2011
    PI(s): David Nesbitt
    Topic(s): Chemical Physics

    The Nesbitt group wants to figure out how chemistry works in outer space. In particular, the group wants to understand the “cosmo”-chemistry leading to the generation of soot, which is similar to products of combustion here on Earth.

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  • Sculpting a Star System: The Inner Planets
    September 22, 2011
    PI(s): Phil Armitage
    Topic(s): Astrophysics

    The Solar System has a remarkable number of planets. It includes four rocky planets (Mercury, Venus, Earth, and Mars), four giant gaseous planets, and countless smaller worlds. Early on, there may even have been a fifth rocky planet that collided with the Earth, forming the Moon. We owe the survival of so many terrestrial planets (and our own evolution as a species) to the relatively stable orbits of Jupiter, Saturn, Uranus, and Neptune during the 100 million years it took to form the inner planets of the Solar System.

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  • Ultracold Polar Molecules to the Rescue!
    September 14, 2011
    PI(s): Ana Maria Rey, Jun Ye
    Topic(s): Atomic & Molecular Physics

    Physicists would very much like to understand the physics underlying high-temperature superconductors. Such an understanding may lead to the design of room temperature superconductors for use in highly efficient and much lower-cost transmission networks for electricity. A technological breakthrough like this would drastically reduce world energy costs. However, this breakthrough requires a detailed understanding of the physics of high-temperature superconductivity.

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  • Hitchhiker’s Guide into the Galaxy
    September 14, 2011
    PI(s): Andrew Hamilton
    Topic(s): Astrophysics

    Long, long ago galaxies now far away formed around ravenous black holes scattered throughout the Universe. Some 12.5 billion years later, JILA scientist Gayler Harford and Fellow Andrew Hamilton have identified the superhighways that funneled gas into some of the nascent galaxies. These thruways not only routed gas to feed the monster black holes, but also supplied raw materials for the billions and billions of stars that have illuminated those galaxies ever since.

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  • The Cold Case
    September 02, 2011
    PI(s): Jun Ye
    Topic(s): Atomic & Molecular Physics

    The Ye group has built a cool new system for studying cold collisions between molecules. The system is far colder than a typical chemistry experiment that takes place at room temperature or hotter (300–500 K). But, it’s also much warmer than experiments that investigate ultracold-molecule collisions conducted at hundreds of billionths of a degree above absolute zero (0 K). The new system is known as “the cold molecule experiment” and operates at temperatures of approximately 5 K (-450 °F).

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  • Probing the Tell-Tale Ions
    August 25, 2011
    PI(s): John Bohn
    Topic(s): Precision Measurement

    JILA’s quest to determine whether the electron has an electric dipole moment (eEDM) began in 2006 with a suggestion by Fellow Eric Cornell that the molecular ion hafnium fluoride (HfF+) might be well suited for an eEDM experiment. An electric dipole moment is a measure of the separation of positive and negative charges in a system. If an electron does have an electric dipole moment, it’s a pretty darn small one. So small, in fact, that if the electron were the size of the Earth, its eEDM would only alter the planet’s roundness by less than the width of a human hair.

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  • Everything is Illuminated
    August 15, 2011
    PI(s): Richard McCray
    Topic(s): Astrophysics

    Supernova 1987A is illuminating its own past. The brightest supernova to light up Earth’s night skies since the Renaissance, it appeared in the southern sky on February 23, 1987 when a blue supergiant star exploded in the Large Magellanic Cloud, a galaxy located 160,000 light years from Earth. For nearly 25 years, Fellow Dick McCray and his colleagues have studied the unfolding story of this remarkable event in the visible, ultraviolet, and x-ray wavelengths. Today, the scientists not only understand the star’s spectacular demise, but also are now learning about the blue supergiant’s chemistry prior to going supernova.

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  • Reactions on Demand
    July 16, 2011
    PI(s): Henry Kapteyn, Margaret Murnane
    Topic(s): Laser Physics

    Predrag Ranitovic dreams of controlling chemical reactions with ultrafast lasers. Now he and his colleagues in the Kapteyn/Murnane group are one step closer to bringing this dream into reality. The group recently used a femtosecond infrared (IR) laser and two extreme ultraviolet (XUV) harmonics created by the same laser to either ionize helium atoms or prevent ionization, depending on experimental conditions. The researchers adjusted experimental conditions to manipulate the electronic structure of the helium atoms as well as control the phase and amplitude of the XUV laser pulses.

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  • The Secrets of the Resonant Lattice
    July 15, 2011
    PI(s): Ana Maria Rey
    Topic(s): Atomic & Molecular Physics

    Theoretical physicists recently combined two powerful tools for exploring ultracold atomic gases: Optical lattices and Feshbach resonances. Optical lattices are crystals of light formed by interacting laser beams. Feshbach resonances in an ultracold atom gas occur at a particular magnetic field strength and cause ultracold atoms to form very large, loosely associated molecules. However, because lattice atoms interact strongly at a Feshbach resonance, the physics of Feshbach resonances in an optical lattice is quite complicated.

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  • Quantum CT Scans
    June 01, 2011
    PI(s): Konrad Lehnert
    Topic(s): Nanoscience, Precision Measurement

    The Lehnert group and collaborators from the National Institute of Standards and Technology (NIST) recently made what was essentially a CT scan of the quantum state of a microwave field. The researchers made 100 measurements at different angles of this quantum state as it was wiggling around. Because they only viewed the quantum state from one angle at a time, they were able to circumvent quantum uncertainties to make virtually noiseless measurements of amplitude changes in their tiny microwave signals. Multiple precision measurements of the same quantum state yielded a full quantum picture of the microwave field.

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  • JILA MONSTR and the Chamber of Secrets
    May 17, 2011
    PI(s): Steven Cundiff
    Topic(s): Nanoscience

    The semiconductor gallium arsenide (GaAs) is used to make tiny structures in electronic devices such as integrated circuits, light-emitting diodes, laser diodes, and solar cells that directly convert light into electrical energy. Because of GaAs’s importance to modern electronics, the Cundiff group seeks to understand the fundamental physics of its light-matter interactions on atomic and electronic levels.

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  • I Sing the Body Electric
    May 11, 2011
    PI(s): Heather Lewandowski
    Topic(s): Chemical Physics

    The Lewandowski group recently decided to see what would happen if it could get cold molecules (1K–1mK) and ultracold (<1mK) atoms to collide. Former graduate student L. Paul Parazzoli, graduate student Noah Fitch, and Fellow Heather Lewandowski devised a novel experiment to determine the collision behavior of cold (100 mK) deuterated ammonia (ND3) molecules and ultracold (600 microK) rubidium (Rb) atoms.

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  • A Flair for Lasing
    May 01, 2011
    PI(s): Chris Greene
    Topic(s): Atomic & Molecular Physics

    Triatomic hydrogen ion (H3+) has many talents. In interstellar clouds, it can be blown apart by free low-energy free electrons, which interact with the ion core (H3+), briefly forming unstable H3 molecules. The interaction of the electron with the ion core almost immediately causes the molecule to fall apart into three hydrogen atoms (3H) or a hydrogen molecule (H2) and an H atom. This reaction is known as dissociative recombination.

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  • Upending Conventional Wisdom
    April 21, 2011
    PI(s): Thomas Perkins
    Topic(s): Biophysics

    In science, it can be fun and interesting to upend conventional wisdom. A good example is what just happened to a widely accepted explanation for overstretching of double-stranded DNA (dsDNA). Overstretching occurs suddenly when researchers add a tiny increment of force to dsDNA that is already experiencing a pulling force of approximately 65 pN. (A piconewton is a trillionth of a newton, which is roughly equal to the gravitational force on a medium-sized apple). The small additional force causes the dsDNA to suddenly become 70% longer — as it stretches like a slinky.

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