Unconventional Bose-Einstein condensation in high orbital bands

ORAL

Abstract

We perform the theoretical study on unconventional Bose-Einstein condensations (UBEC) in higher orbital bands of optical lattices observed by Hemmerich's group. These exotic states of bosons are non-zero condensation wavevectors, and thus beyond the ``no-node'' paradigm. We have studied various effects on UBECs including lattice asymmetry and interactions. The interplay between the kinetic and interaction energies gives rise to two different UBECs with the real and complex-valued condensation wavefunctions, respectively. The latter spontaneously breaks time-reversal symmetry, which is impossible in usual BEC systems.

–

Authors

  • Congjun Wu

    • The department of Physics, Univeristy of California, San Diego
    • The Department of Physics, Univeristy of California, San Diego
    • The Department of Physics, University of California, San Diego
    • Department of Physics, University of California, San Diego
    • UC San Diego
    • The Department of Physics, University of Science and Technology of China
    • University of California, San Diego

  • Zi Cai

    • The department of Physics, Univeristy of California, San Diego
    • UC San Diego
    • The Department of Physics, University of California, San Diego

  • Andreas Hemmerich

    • Institut f\"ur Laser-Physik, Universit\"at Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany