Softening of roton and phonon modes in a Bose-Einstein condensate with spin-orbit coupling

Si-Cong Ji1, Long Zhang1, Xiao-Tian Xu1

  • 1Shanghai Branch, Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.

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