The Regal group recently met the challenge of measurements in an extreme situation with a device called an interferometer. The researchers succeeded by using creative alterations to the device itself and quantum correlations. Quantum correlations are unique, and often counterintuitive, quantum mechanical interactions that occur among quantum objects such as photons and atoms. The group...
Precision Measurement
Content About: Precision Measurement
The first results are in from a new search for the axion, a hypothetical particle that may constitute dark matter. Researchers in the Haloscope At Yale Sensitive to Axion Cold Dark Matter (HAYSTAC) recently looked for evidence of the axion, but so far they have found none in the small 100 MHz frequency range between 5.7 and 5.8 GHz.
The experiment relied on the Lehnert group’s microwave...
Research associate Shimon Kolkowitz and his colleagues in the Ye group and Rey theory group have developed a powerful new way to experimentally simulate the complex behavior of electrons in solids. In these experiments, the team uses its strontium lattice optical clock not to track time, but to take advantage of the ultracold atoms in the clock mimicking the quantum behavior of electrons in a...
Bob Peterson and his colleagues in the Lehnert-Regal lab recently set out to try something that had never been done before: use laser cooling to systematically reduce the temperature of a tiny drum made of silicon nitride as low as allowed by the laws of quantum mechanics. Although laser cooling has become commonplace for atoms, researchers have only recently used lasers to cool tiny silicon...
Fellow Judah Levine recently presented a discussion of our understanding of time from antiquity to the present day in an insightful paper published in the April 2016 issue of the European Physical Journal H.
Levine recounted that for at least 7000 years, the measurement of time has been linked to the rotation of the Earth, the lunar cycle, the path of the Earth around the Sun, and other...
The Ye and Rey groups have discovered the strange rules of quantum baseball in which strontium (Sr) atoms are the players, and photons of light are the balls. The balls control the players by not only getting the atoms excited, but also working together. The players coordinate throwing and catching the balls. While this is going on, the balls can change the state of the players! Sometimes the...
President Obama has selected JILA Fellow Jun Ye of NIST's Quantum Physics Division to receive a 2015 Presidential Rank Award. The award cited Ye's work advancing "the frontier of light-matter interaction and focusing on precision measurement, quantum physics and ultracold matter, optical frequency metrology, and ultrafast science."
The Presidential Rank Awards honor a select group...
Deborah Jin and Jun Ye are Highly Cited Researchers for 2015, according to the Thomas Reuters website. The website states, "Highly Cited Researchers 2015 represents some of world’s most influential scientific minds. About three thousand researchers earned this distinction by writing the greatest number of reports officially designated by Essential Science Indicators as Highly Cited Papers—...
Jun Ye gave a fascinating talk entitled "Let There Be Light (and Thus, Time)" at a DARPA conference on Friday Sept. 11 in St. Louis. Ye described how ultrasensitive lasers can measure the very nature of time as well as the ever-changing distance between the Earth and the Moon. Ye's talk was highlighted the following week in a Sept. 15 article by Rebecca Boyle in...
Richard Bowman has highlighted the Perkins Lab's recent Optics Express paper entitled "Ultrastable measurement platform: sub-nm drift over hours in 3D at room temperature" in the Optical Society of America's (OSA's) August 2015 Spotlight on Optics. Spotlight on Optics features articles of wide interest that have been recently published in OSA journals. This article provides background...
The Ye group has just improved the accuracy of the world’s best optical atomic clock by another factor of three and set a new record for clock stability. The accuracy and stability of the improved strontium lattice optical clocks is now about 2 x 10-18, or the equivalent of not varying from perfect time by more than one second in 15 billion years—more than the age of the Universe. Clocks like...
APS Physics has produced a lovely story entitled The World's Time by Andrei Derevianko on its Forum on International Physics. The story features Judah Levine, Jun Ye and other scientists from around the world.
Graduate student Adam Kaufman and his colleagues in the Regal and Rey groups have demonstrated a key first step in assembling quantum matter one atom at a time. Kaufman accomplished this feat by laser-cooling two atoms of rubidium (87Rb) trapped in separate laser beam traps called optical tweezers. Then, while maintaining complete control over the atoms to be sure they were identical in every...
The Ye group has not only made two invisible rulers of extreme ultraviolet (XUV) light, but also figured out how to observe them with ordinary laboratory electronics. With this setup, the researchers were able to prove that the two rulers had extraordinarily long phase-coherence time. This feat is so profound, it is nearly certain to transform the investigation of matter with extreme...
Thomas Perkins received the 2013 Arthur S. Flemming Award at a Washington, D. C., ceremony on June 9. The award was one of 12 given this year to honor outstanding Federal employees in their first 15 years of Federal service. Dr. David Bray, Chief Information Officer for the Federal Communications Commission and a 2012 Flemming Award winner, was the keynote speaker at the event.
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Imagine a network of multiple clocks orbiting the Earth, not only reporting down to us, but also collaborating quantum mechanically among themselves to operate precisely in sync as a single global superclock, or world clock. The world clock is delivering the most precise timekeeping in all of human history—to every member nation regardless of politics, alliances, or behavior on the ground....
Cindy Regal has been selected to receive a 2014 Cottrell Scholars Award from the Research Corporation for Science and Advancement. The Cottrell Scholar Awards are given to early career faculty members who excel at both research and teaching. The awards target scholarship designed to improve undergraduate science education at research universities in the United States.
JILA and NIST labs are well on the way to creating astonishingly accurate optical atomic clocks based on the neutral atoms strontium (Sr) and ytterbium (Yb). The new technologies are already capable of the most meticulous timekeeping in human history.
JILA Fellow Jun Ye’s group has developed an optical atomic clock that uses neutral Sr atoms held in an optical lattice (i.e., crystal of...
Steve Cundiff was named an IEEE Fellow on January 1, 2014. In electing him as a Fellow, the Board of Directors of the Institute of Electrical and Electronics Engineers, Inc. cited him "for contributions to self-referenced optical frequency combs and ultrafast nonlinear solid-state spectroscopy."
"I am delighted to share the good news with you and to congratulate you on having this...
Physicists wonder about some pretty strange things. For instance, one burning question is: How round is the electron? While the simplest picture of the electron is a perfect sphere, it is possible that it is instead shaped like an egg. The egg shape would look a bit like a tiny separation of positive and negative charges. Physicists call this kind of charge separation an electric dipole moment...
Research associate Tom Purdy and his colleagues in the Regal group have just built an even better miniature light-powered machine that can now strip away noise from a laser beam. Their secret: a creative workaround of a quantum limit imposed by the Heisenberg Uncertainty Principle. This limit makes it impossible to simultaneously reduce the noise on both the amplitude and phase of light inside...
Graduate student Travis Nicholson (Ye group) handily won the competition for Best Student Paper at the joint symposium of the IEEE-International Frequency Control Symposium (IFCS), the IEEE-International Ultrasonics Symposium (IUS), the IEEE-International Symposium on the Applications of Ferroelectric (ISAF) and the Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar...
Judah Levine received the IEEE Ultrasonics, Ferroelectrics, and Frequency Control Society Rabi Award on July 24 during a joint symposium on time and frequency held in Prague, Czech Republic. Participants included the IEEE-International Frequency Control Symposium (IFCS), the IEEE-International Ultrasonics Symposium (IUS), the IEEE-International Symposium on the Applications of Ferroelectric (...
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...
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. The group has shown that gold-coated probes are a...
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. This impressive result was obtained by lead graduate student Travis Nicholson, graduate students Mike...
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. Interferometers are widely used...
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...
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 Paradox Derails Unwanted Collisions
In 2008-2009, much to their amazement,researchers working on the Jun Ye group’s neutral Sr optical atomic clock discovered tiny frequency shifts caused by colliding fermions! They figured out that the clock laser was interacting slightly differently with the Sr atoms inside a one-dimensional (pancake-shaped) trap. The light-atom...
Of all the fundamental forces, gravity is the most difficult to precisely measure. This difficulty is reflected in how hard it is to accurately measure “Big G,” a fundamental constant that is part of the measurement of the gravitational force. In fact, big G is the least precisely measured fundamental constant in physics. Who would have imagined that the very first fundamental...
The secret for reducing quantum noise in a precision measurement of spins in a collection of a million atoms is simple: Pre-measure the quantum noise, then subtract it out at the end of the precision measurement. The catch is not to do anything that detects and measures the spins of individual atoms in the ensemble. If states of individual atoms are measured, then those atoms stop being in a...
Dr. John Hall shares some of his thoughts and experiences developing the optical frequency comb, the discovery for which he shared the 2005 Nobel Prize. The occasion was the 2010 (Colorado) Governor's Award for High Impact Research, sponsored by CO-LABS.
The winner of the 2005 Nobel Prize in Physics reflects on a career spent with a fascination for lasers and science. John L. Hall is a fellow and senior research associate at JILA, a joint institute of the University of Colorado at Boulder and the National Institute of Standards and Technology. He was awarded the 2005 Nobel Prize in Physics.
Hall is known as a pre-eminent laser...
The Dana Z. Anderson group has developed a microchip-based system that not only rapidly produces Bose-Einstein condensates (BECs), but also is compact and transportable. The complete working system easily fits on an average-sized rolling cart. This technology opens the door to using ultracold matter in gravity sensors, atomic clocks, inertial sensors, as well as in electric- and magnetic-field...
Not content with stepping on their bathroom scales each morning to watch the arrow spin round to find their weights, former research associate John Teufel and Fellow Konrad Lehnert decided to build a nifty system that could measure more diminutive forces of half an attoNewton (0.5 x 10-18 N). Their new system consists of a tiny oscillating mechanical wire embedded in a microwave cavity with an...
The race to measure the electron’s electric dipole moment (eEDM) is picking up speed across the world, thanks to graduate student Ed Meyer of JILA’s Lazy Bohn’s Ranch (i.e., John Bohn’s theory group). Meyer has identified more than a dozen horses, a.k.a. molecules and molecular ions, with strong enough internal electric fields to compete in the eEDM derby. Imperial...
The Anderson and Cornell groups have adapted two statistical techniques used in astronomical data processing to the analysis of images of ultracold atom gases. Image analysis is necessary for obtaining quantitative information about the behavior of an ultracold gas under different experimental conditions. Until now, the preferred method has been to find a shape (such as a Gaussian) that...
According to the laws of quantum mechanics, identical fermions at very low temperatures can’t collide. These unfriendly subatomic particles, atoms, or molecules simply will not share the same piece of real estate with an identical twin. A few years back, researchers in the Ye lab considered this unneighborly behavior a big advantage in designing a new optical atomic clock based on an ensemble...
Last year the Ye group conducted an actual laboratory astrophysics experiment. Graduate students Brian Sawyer, Ben Stuhl, and Mark Yeo, research associate Dajun Wang, and Fellow Jun Ye fired cold hydroxyl (OH) radicals into a linear decelerator equipped with an array of highly charged electrodes and slowed the OH molecules to a standstill. These molecules were then loaded into a permanent...
In the summer of 2008, Fellow Jun Ye spent a couple of months at CalTech, where he ran into another visiting professor, former JILA Fellow Peter Zoller. Zoller left JILA in 1994 to become Professor of Physics at the University of Innsbruck (Austria). Besides riding bikes together in the mountains, the two men engaged in happy and fruitful discussions about Ye’s work developing a strontium- (Sr...
In a rural northern Colorado landscape punctuated by plentiful corn fields, a tree farm, an abandoned feedlot, and a handful of McMansions, only one thing is certain: the exact time. The nation’s backup time scale, consisting of four atomic clocks, two measurement systems, and supporting hardware is tucked away inside radio station WWV's remote transmission station, located 12...
Fellow Konrad Lehnert needed a virtually noiseless amplifier to help with his experiments on nanoscale structures, so he invented one. Working with graduate student Manuel Castellanos-Beltran and NIST scientists Kent Irwin, Gene Hilton, and Leila Vale, he conceived a tunable device that operates in frequencies ranging from 4 to 8 GHz. This device has the lowest system noise ever measured for...
Nanoartisans Cindy Regal, John Teufel, and Konrad Lehnert have come up with a clever new way to observe ordinary (very small) things behaving quantum mechanically. They’ve tucked a nanomechanical beam (which is actually a really thin aluminum wire) inside a tiny resonant microwave cavity made of lightweight superconducting aluminum. This design ensures that very small forces will cause...
Fellow Jun Ye’s group is methodically working its way toward the creation of an X-Ray frequency comb. Recently, senior research associate Thomas Schibli, graduate student Dylan Yost, Fellow Jun Ye, and colleagues from IMRA America, Inc. developed a high-performance, ultrastable fiber laser optical frequency comb. At the same time, Yost developed a clever method for getting coherent short-...
What sort of experiment could detect the effects of quantum gravity, if it exists? Theories that go beyond the Standard Model of physics include a concept that links quantum interactions with gravity. Physicists would very much like to find evidence of this coupling as these two branches of physics are not yet unified in a single theory that explains everything about our...
By late 2006, Fellow Jun Ye’s clock team had raised the accuracy of its strontium (Sr)-lattice atomic clock to be just shy of that of the nation’s primary time and frequency standard, the NIST-F1 cesium (Cs) fountain clock. Graduate students Marty Boyd and Andrew Ludlow led the effort to improve the clock’s accuracy. But then, the clock team had to spend another year proving that its imporved...
With every breath you take, you breathe out carbon dioxide and roughly 1000 other different molecules. Some of these can signal the early onset of such diseases as asthma, cystic fibrosis, or cancer. Thanks to graduate student Mike Thorpe and his colleagues in Fellow Jun Ye’s group, medical practitioners may one day be able to identify these disease markers with a low-cost, noninvasive breath...
In the quantum world inside Fellow Eric Cornell’s lab, communication occurs across a two-dimensional lattice array of Bose-Einstein condensates (BECs) when atoms tunnel out of superatoms (made from about 7000 garden-variety rubidium (Rb) atoms) into neighboring BECs. This communication keeps the array coherent, i.e., the phases of all condensates remain locked to each other. But something...
Small changes in the quantum fluctuations of free space are responsible for a variety of curious phenomena: a gecko’s ability to walk across ceilings, the evaporation of black holes via Hawking radiation, and the fact that warmer surfaces can be stickier than cold ones in micro- and nanoscale electromechanical systems (MEMS and NEMS). The tendency of tiny parts to stick together is a...
JILA Fellow Dana Z. Anderson, JILA visiting scientist Alex Zozulya, and a colleague from the Worcester Polytechnic Institute postulate that the ultracold coherent atoms in a Bose-Einstein Condensate (BEC) could be configured to act like electrons in a transistor. An “atom transistor” would exhibit absolute and differential gain, as well as allow for the movement of single atoms to be resolved...
A key challenge in developing new nanotechnologies is figuring out a fast, low-noise technique for translating small mechanical motions into reasonable electronic signals. Solving this problem will one day make it possible to build electronic signal processing devices that are much more compact than their purely electronic counterparts. Much sooner, it will enable the design of advanced...
When will the Laser Interferometer Space Antenna (LISA) fly? Fellows Jim Faller and Peter Bender first proposed the basic concept behind LISA more than 25 years ago. The joint European Space Agency/NASA mission first scheduled a possible launch in 2012. The date has now slipped to 2017, with additional delays possible. Both agencies are grappling with limited budgets and conflicting...
When Albert Einstein said, "the only reason for time is so that everything doesn't happen at once," he didn't know about studies performed by Senior Research Associate Christine Hackman and Fellow Judah Levine. These time-and-frequency experts work quite hard to devise ways of comparing the accuracy and stability of the world's premier atomic clocks - so that things like satellite...
Graduate students Dave Harber and John Obrecht, postdoc Jeff McGuirk, and Fellow Eric Cornell recently devised a clever way to use a Bose-Einstein condensate (BEC) inside a magnetic trap to probe the quantum behavior of free space. To do this, the researchers first created a BEC inside a magnetic trap, whose shape (where the condensate forms) resembles a cereal bowl. Then as shown in the...
Fellow Jan Hall has been working on stabilizing the frequency of lasers since the 1960s. Now, he, JILA Research Associate Mark Notcutt, Long-Sheng Ma (currently at BIPM in France), and Fellow Jun Ye have devised an improved, compact, and less expensive method for stabilizing lasers. The new method is based on a small, vertically mounted optical cavity (shown on the right). Because the cavity...
Three years ago Jun Ye decided to apply an old idea for amplifying and stabilizing continuous-wave (cw) lasers to state-of-the-art ultrafast lasers. In 2002, Jason Jones, a postdoctoral fellow with Jun, analyzed whether the build-up cavities used to amplify cw laser outputs could be modified to work with ultrafast, mode-locked lasers. His detailed calculations suggested that it would be...
Pete Roos, Tara Fortier, Xiaoqin Li, Ryan Smith, Jessica Pipis, and Steve Cundiff are using a phase-controlled mode-locked laser to control quantum processes in semiconductors. Semiconductors are capable of producing electrical currents from light (and vice-versa) and are the basis for a wide variety of optoelectronic devices, including photodiodes, light-emitting diodes, and solar cells....
Plans for the Development of a Portable Absolute Gravimeter with the Few Parts in a Billion Accuracy
