Bose-Einstein Condensation (BEC)

BEC is a unique soft condensed matter system with a vast number of aspects to be studied. So far, I have studied some of the more fundamental issues relating to BEC. Some of these include the study of the damping of quasiparticle excitations, time-dependent dynamics based on Hartree-Fock-Bogoliubov theory, determination of the quantum many-body wave function, analogies with the quantum Hall effect, and the quantum entanglement resulting from intrinsic interatomic interactions.

Superfluidity; Vortex Matter

One of the most fruitful areas of study in Physics is the study of superfluidity. BEC is a novel superfluid system which exhibits many of the properties which can not be easily tested and confirmed in Helium-4. In particular, I have studied dynamical formation of vortices and the detailed structure of the elementary excitations of vortex lattices including the Tkachenko, hydrodynamic bulk, and surface modes.

Atom Lasers; Quantum Control

BEC may also be viewed as a highly intense source of coherent atoms with a well-defined phase, just as a laser is a source of coherent, high-intensity photons. In this context, I have studied rudimentary BEC atom optics, output coupling of BEC from its confining trap potential, spatio-temporal interferometry "quantum carpet" of BEC, quantum nondemolition measurement using BEC, and various methods to quantum control a BEC.

Initial steps towards quantum control of atomic Bose-Einstein condensates

S. Choi and N. P. Bigelow,

J. Opt. B: Quant. Semiclass. Opt. 7, S413 (2005)

Excitation spectroscopy of vortex lattices in a rotating Bose-Einstein condensates

S. J. Woo, L. O. Baksmaty, S. Choi, and N. P. Bigelow

Phys. Rev. Lett. 92, 170402 (2004)

Tkachenko waves in rapidly rotating Bose-Einstein condensates

L. O. Baksmaty, S. J. Woo, S. Choi, and N. P. Bigelow,

Phys. Rev. Lett. 92, 160405 (2004)

Geometric phases of macroscopic spin in Bose-Einstein Condensates

I. Fuentes-Guridi, J. Pachos, S. Bose, V. Vedral, and S. Choi,

Phys. Rev. A 66, 022102 (2002)

Coherent output, stimulated quantum evapouration and pair breaking in a trapped atomic Bose gas

Y. Japha, S. Choi, K. Burnett, and Y. B. Band,

Phys. Rev. Lett. 82, 1079 (1999)

Non-linear mixing of quasiparticles in inhomogeneous Bose condensate

S. A. Morgan, S. Choi, K. Burnett, and M. Edwards

Phys. Rev. A 57, 3818 (1998)