Laboratory Administrator: Gina Yildirim

The Ni research group is working to create molecules at the lowest possible temperatures, and to study their chemical reactions and physical interactions.  At such ultra-cold temperatures, quantum mechanics describes all aspects of the molecules: their position, orientation, and internal state.  In this fascinating regime, new quantum phases emerge, beyond the usual gas, liquid, and solid phase, and even Bose-Einstein condensation.  These phases are the subject of many theoretical studies, and now await laboratory demonstration.  At ultra-cold temperatures, chemistry is also fully quantum mechanical, and unusual four-center reactions may dominate chemical dynamics.  We are embarking to map out this strange new world of ultra-cold quantum chemistry and ultra-cold molecules.

Kang-Kuen joined Harvard as an assistant professor in 2013.  She obtained her B.S. in physics from the University of California, Santa Barbara, and her Ph.D. in physics from the University of Colorado, Boulder. Her doctoral dissertation, completed under the supervision of Prof. Deborah Jin and Prof. Jun Ye, describes the first experimental realization of an ultra-cold, near-quantum-degenerate gas of polar molecules.

Selected Publications:

K.-K. Ni, S. Ospelkaus, M. H. G. de Miranda, A. Pe’er, B. Neyenhuis, J. J. Zirbel, S. Kotochigova, P. S. Julienne, D. S. Jin, and J. Ye. A High Phase-Space-Density Gas of Polar Molecules. Science, 322:231, 2008.

S. Ospelkaus, K.-K. Ni , G. Quéméner, B. Neyenhuis, D. Wang, M. H. G. de Miranda, J. L. Bohn, J. Ye, and D. S. Jin. Controlling the Hyperfine State of Rovibronic Ground-State Polar Molecules. Phys. Rev. Lett., 104(3):030402, 2010.

S. Ospelkaus, K.-K. Ni , D. Wang, M. H. G. de Miranda, B. Neyenhuis, G. Quéméner, P. S. Julienne, J. L. Bohn, D. S. Jin, and J. Ye. Quantum-State Controlled Chemical Reactions of Ultracold Potassium-Rubidium Molecules. Science, 327:853, 2010.

K.-K. Ni, S. Ospelkaus, D. Wang, G. Quéméner, B. Neyenhuis, M. H. G. de Miranda, J. L. Bohn, J. Ye, and D. S. Jin. Dipolar collisions of polar molecules in the quantum regime. Nature, 464:1324–1328, 2010.

K.-K. Ni, R. Norte, D. J. Wilson, J. D. Hood, D. E. Chang, O. Painter, and H. J. Kimble. Enhancement of Mechanical Q Factors by Optical Trapping. Phys. Rev. Lett., 108(21):214302, 2012.