Jun Ye was born in Shanghai, China, in 1967. His father was a naval officer who later pursued a career in business. His mother was an environmental scientist and city official who controlled funding for environmental protection. While his parents were busy with their careers, Ye grew up in Shaoxing, a city about 200 km south of Shanghai. He was raised by his father’s mother, E-Gui Jin, who placed such a high value on education that he would dedicate his Ph.D. thesis to her in 1997.
Ye says his generation had many more educational opportunities after Mao Zedong died in 1976. Ye and his contemporaries were too young to be affected by the Cultural Revolution, which had incited widespread destruction of much China’s traditional cultural heritage. Ye also reaped the benefits of a strong revival of China’s national educational system in the late 1970s.
His own interest in science began as a freshman in high school when he began reading profiles of leading physicists in Chinese journals. After reading about the life of Erwin Schrödinger, he remembers thinking “what an interesting life he had lived.” At about the same time, he had to make a difficult decision between an educational path emphasizing science and technology and another emphasizing literature. Soon after deciding upon the science and technology path, he was selected to represent his high school in a national physics competition. “I did reasonably well, especially on the experimental part where I was told to figure out problems with a non-functioning Wheatstone Bridge circuit,” he recalls. “And, I discovered that physics was exciting for me. I decided that I would go to college and study physics.”
Ye earned a Bachelor’s degree in physics at Shanghai Jiao-Tong University in 1989. His courses were mostly in theory until his undergraduate thesis, which was based on work performed in an optics laboratory. This work led to Ye’s first publication in the journal Applied Optics (in 1990). At Jiao-Tong, Ye was an excellent student. He expected to travel a smooth path to graduate school and a career as a physicist in China.
The student uprising and turmoil of the spring 1989 changed his plan. “We were very idealistic at the time, and who wouldn’t be at a young age” he says. “We wanted an open society immediately. And, perhaps we were a bit too impatient.”
Being disappointed, in late 1989 Ye came to the United States to work on quantum optics theory with Marlan Scully at the University of New Mexico. He also started an experimental career with John McInerney on semiconductor lasers. One summer he had the opportunity to work with Howard Bryant on high-energy beam collisions involving negative ions at Los Alamos National Laboratory. By the time Scully announced he was moving to Texas, Ye had earned a Master’s degree in physics from New Mexico (1991). He also knew he wanted to pursue a hardcore experimental career in AMO physics. He began looking around and discovered an experimental genius at JILA named Jan Hall. “I told Jan, ‘I want to be your student,’” Ye recalls.
“Jan said, ‘You must be very brave.’” Hall accepted Ye (in 1992) as the last graduate student to enter his research group. For his thesis, Ye worked on high-resolution and high-sensitivity molecular spectroscopy. He profited from Hall’s technical wizardry every step of the way.
“The molecule work was very difficult,” Ye recalls. “At room temperature, molecules fly around all over the place. You can see why I decided later on to study cold molecules, which stay put long enough to enable precision study.” Ye’s graduate work was a resounding success and laid the foundation for his career as an experimental physicist. He earned his Ph. D. from the University of Colorado in 1997.
His next stop was as a Millikan postdoctoral fellow in experimental quantum optics in Jeff Kimble’s lab at CalTech. Kimble’s lab was another formative experience. There, Ye was given the assignment of developing a single atom trap in a tiny optical cavity, some space in the lab, and a million dollars to spend. He was given a year to work out the technical details on his own. He thrived as part of a large group with young scientists from all over the world. He liked it so much, in fact, that he subsequently encouraged Associate Fellow Cindy Regal and former graduate student Kang-Kuen Ni to do their own postdocs in Kimble’s lab.
Ye returned to JILA in 1999 as an Associate Fellow. His thesis advisor and mentor Hall donated most of his laboratory space to him. That year was a starting point for the rapid development of optical frequency combs based on ultrafast lasers, and Ye got to work closely with both Steve Cundiff and Jan Hall. It was a great experience for the JILA scientists to marry two once-separated fields of precision single-frequency lasers and ultrafast optical science.
Ye also began working on a new optical atomic clock based on neutral strontium atoms and started another program on cold molecules. In 2001, he became a Fellow of JILA. Today, he directs a large group of 18 young scientists from all over the world. The group recently began using a second Sr-lattice clock to explore the frontier of light-matter interactions at the quantum level.
Currently the Ye group does research in three key areas: (1) the physics of strontium (Sr) atoms, including the development and enhancement of a neutral Sr optical atomic clock and Sr-based quantum simulations for novel quantum many-body systems; (2) research on the behavior and chemistry of cold and ultracold molecules, including a collaboration with Deborah Jin on using ground-state potassium-rubidium (KRb) molecules as a quantum simulator and a study of collisions of ammonia and other molecules at milliKelvin temperatures; and (3) precision spectroscopy, including the precision measurement of fundamental constants and the expansion of optical frequency comb technology into higher- and lower-frequency regions of the electromagnetic spectrum. One team in the Ye group is currently investigating frequency combs in the mid-infrared and extreme ultraviolet regions. Another team collaborates with Eric Cornell on using frequency combs to map out unknown molecular structures as part of the search for the electron electric dipole moment. Ye also enjoys great collaborations with many JILA theorists, including John Bohn, Murray Holland, and Ana Maria Rey.
Ye has earned many awards for his scientific accomplishments, including the 1999 OSA Adolph Lomb Medal, a 2002 Technology Review Magazine's TR100 Young Innovator, a 2003 Presidential Early Career Award in Science and Engineering, the 2005 Arthur S. Flemming Award, the 2006 NIST Samuel W. Stratton Award, the 2006 William F. Meggers Award from the Optical Society of America, the 2007 I.I. Rabi Prize from the American Physical Society, the 2007 Friedrich Wilhelm Bessel Research Award from the Alexander von Humboldt Foundation, the 2007 Carl Zeiss Award, two Department of Commerce Gold Medals (in 2001 and 2011), the 2009 European Time and Frequency Forum Award, and a 2011 Frew Fellowship. Ye was named a Gordon and Betty Moore Distinguished Scholar by CalTech in 2008 and elected Direcctor at Large of the Optical Society of America in 2011. He is a Fellow of the National Institute of Standards and Technology, the American Physical Society, and the Optical Society of America as well as a member of the National Academy of Sciences.
Ye is married to Ying Zhang, whom he knew as a child when her family were neighbors of his grandmother in Shanghai. The couple has two daughters, one in elementary school and the other a student at the University of Colorado. The Ye family enjoys music, hiking, and visiting libraries, churches, and museums in the United States, Europe, and China. The family enjoys their Chow/Golden-mix dog.