About the Ye Group
Quantum science and precision metrology — quantum matter probed with novel light source
Our research group explores the frontier of light-matter interactions. Precisely controlled lasers enable our communications with microscopically engineered quantum systems of atoms and molecules. By preparing matter in specific quantum states, and using probe light with the longest coherence time and precisely controlled waveform, we strive to make fundamental scientific discoveries and develop new enabling technologies.
The strongly integrated development of scientific vision and experimental tools has enabled us to advance important topics in precision measurement, quantum many-body physics, quantum metrology, ultrafast science, and quantum science in general. For example, we employ quantum gas of strontium atoms confined in optical lattices to achieve best performing atomic clocks and investigate novel quantum dynamics, combining quantum metrology and quantum simulation. We prepare molecules in quantum degenerate gases to engineer tunable Hamiltonians for correlated quantum phenomena. These quantum-state prepared molecules are also explored for test of fundamental physics and study of quantum chemistry. Stable lasers and optical frequency combs are extending precision spectroscopy and extreme nonlinear optics from mid infrared to extreme ultraviolet, providing novel probes for large quantum systems, trace detection for health and environment, and new spectroscopy opportunities for nuclear transitions.
Our group explores many facets of ultracold strontium (Sr), emphasizing precision measurement and quantum state engineering and manipulation of atomic states. The group has achieved exquisite technical control via precision stabilization of lasers and the realization of ultracold atoms in optical lattices. Early on, we focused on precision measurements of Sr electronic transitions, which occur at optical frequencies, to explore the possibility of developing an optical atomic clock.
Since 1999 and 2000, there has been a remarkable convergence of the fields of ultrafast optics, opti cal frequency metrology, and precision laser spectroscopy — a convergence that our lab was privileged to help facilitate. A remarkable transformation took place in these fields as unprecedented advances occurred in the control of optical phases ranging from the ultrashort (femtoseconds) to laboratory time scales (seconds). Today, a single-frequency continuous optical field can achieve a phase coherence time exceeding 1 s. This phase coherence can be precisely transferred to the electric waveform of an ultrafast pulse train!
Molecules cooled to ultralow temperatures provide fundamental new insights to molecular interaction dynamics in the quantum regime. In recent years, researchers from various scientific disciplines such as atomic, optical, and condensed matter physics, physical chemistry, and quantum science have started working together to explore many emergent research topics related to cold molecules, including cold chemistry, strongly correlated quantum systems, novel quantum phases, and precision measurement. The exceedingly low energy regimes for ultracold molecules represent a new playground for chemical physics where quantum behaviors play a dominant role in molecular interaction and dynamics. Unique and complex molecular energy structure provides new opportunities for sensitive probe of fundamental physics. The anisotropic and long-range dipolar interactions add new ingredients to strongly correlated and collective quantum dynamics in many-body systems.
Stories About Our Research
In the Spotlight
Walk down to the basement labs of JILA and you're sure to find something interesting. From atomic clocks to biophysics, researchers are hard at work advancing scientific and technological frontiers. One of these researchers is graduate student Dhruv Kedar. Kedar works in JILA and NIST Fellow Jun Ye's lab, focusing on laser development for a range of applications including optical atomic clocks and optical timescales. “We're really just trying to make the world's best lasers as part of the atomic clock,” explained Kedar. “We do a good job of isolating out any sort of environmental effects so the atomic frequency of the clock doesn't change but gets more precise.” As optical atomic clocks use a series of lasers to control and measure the quantum state evolution inside an atom, which will redefine the SI unit of Second in the foreseeable future, improving the lasers to be themselves free of environmental noise is an important task.
The DoD announced today the selection of nine distinguished faculty scientists and engineers for the 2022 Class of Vannevar Bush Faculty Fellows (VBFF). This highly competitive Fellowship is named in honor of Dr. Vannevar Bush, who directed the Office of Scientific Research and Development after World War II. In line with Dr. Bush’s vision, the Fellowship aims to advance transformative, university-based fundamental research.
“The Vannevar Bush Faculty Fellowship is the Department’s most prestigious research grant award,” said Dr. Jean-Luc Cambier, the VBFF Program Director. “It is oriented towards bold and ambitious ‘blue sky’ research that will lead to extraordinary outcomes that may revolutionize entire disciplines, create entirely new fields, or disrupt accepted theories and perspectives.” JILA and NIST Fellow Jun Ye has been distinguished as one of the 2022 Fellows.
This year, JILA celebrates its 60th anniversary. Officially established on April 13, 1962, as a joint institution between the University of Colorado Boulder and the National Institute of Standards and Technology (NIST), JILA has become a world leader in physics research. Its rich history includes three Nobel laureates, groundbreaking work in laser development, atomic clocks, underlying dedication to precision measurement, and even competitive sports leagues. The process of creating this science goliath was not always straightforward and took the dedication and hard work of many individuals.
“It's hard to imagine my career without JILA,” explained Mike Martin, staff scientist at Los Alamos National Laboratory. Martin first arrived at CU in 2006, as a graduate student. “I began working with [JILA and NIST Fellow] Jun Ye in 2007,” he said. “My work was in frequency metrology for precision measurement and timekeeping.” During Martin's stint at JILA, he explained that he helped work on the early development of the frequency comb. As time continued, his work expanded to include studying the strontium lattice clock. “At the time there was only one strontium apparatus in Jun’s lab,” he said. “And around 10 people or so were all studying it.” This allowed him to collaborate with many other colleagues on the science behind the clock.