We develop a symmetry classification scheme to find ground states of pseudo-spin- $\frac{1}{2}$ , spin-1, and spin-2 spin-orbit-coupled spinor Bose-Einstein condensates and show that as the SO(2) symmetry of simultaneous spin and space rotations is broken into discrete cyclic groups, various types of lattice structures emerge in the absence of a lattice potential. Examples include two different kagome lattices for pseudo-spin- $\frac{1}{2}$ condensates and a nematic vortex lattice in which uniaxial and biaxial spin textures align alternatively for spin-2 condensates. For the pseudo-spin- $\frac{1}{2}$ system, although mean-field states always break time-reversal symmetry, there exists a time-reversal invariant many-body ground state, which is fragmented and expected to be observed in a microcondensate.We develop a symmetry classification scheme to find ground states of pseudo-spin-$\frac{1}{2}$, spin-1, and spin-2 spin-orbit-coupled spinor Bose-Einstein condensates and show that as the SO(2) symmetry of simultaneous spin and space rotations is broken into discrete cyclic groups, various types of lattice structures emerge in the absence of a lattice potential. Examples include two different kagome lattices for pseudo-spin-$\frac{1}{2}$ condensates and a nematic vortex lattice in which uniaxial and biaxial spin textures align alternatively for spin-2 condensates. For the pseudo-spin-$\frac{1}{2}$ system, although mean-field states always break time-reversal symmetry, there exists a time-reversal invariant many-body ground state, which is fragmented and expected to be observed in a microcondensate.

arXiv:1203.2005Physical Review ASep 26, 201274 citations

Ground-State Properties of a Dilute Two-Dimensional Bose Gas

V. Pastukhov

arXiv:1803.05242Journal of Low Temperature PhysicsOct 12, 20187 citations

Ground-state energy and depletions for a dilute binary Bose gas (10 pages)

André Eckardt

Physical Review AJan 1, 20040 citations

Quantum state of two coupled Bose-Einstein condensates

Michael J. Steel, Matthew J. Collett, Daniel F. Walls +1 more

Summary form only given.Due to interatomic collisions, the ground state of a Bose-Einstein condensate of dilute atoms is not, as is commonly assumed, a coherent state. First recognizing this point, Lewenstein and You concluded that the condensate is actually an amplitude quadrature eigenstate. We have extended this work by studying the quantum state for two condensates with a linear coupling provided by either spatial tunneling or laser coupling between magnetic substates. As the system is closed, the ground state is unambiguously a pure state, and as we deal only with relative phases, there is no need to invoke broken symmetry.Summary form only given.Due to interatomic collisions, the ground state of a Bose-Einstein condensate of dilute atoms is not, as is commonly assumed, a coherent state. First recognizing this point, Lewenstein and You concluded that the condensate is actually an amplitude quadrature eigenstate. We have extended this work by studying the quantum state for two condensates with a linear coupling provided by either spatial tunneling or laser coupling between magnetic substates. As the system is closed, the ground state is unambiguously a pure state, and as we deal only with relative phases, there is no need to invoke broken symmetry.

Conference on Lasers and Electro-OpticsNov 27, 20020 citations

The ground state of Bose gases with repulsive interaction: A quantum Monte Carlo study

Wirawan Purwanto, Shiwei Zhang

Bulletin of the American Physical SocietyMar 22, 20050 citations

We develop a symmetry classification scheme to find ground states of pseudo-spin-

\frac{1}{2}

, spin-1, and spin-2 spin-orbit-coupled spinor Bose-Einstein condensates and show that as the SO(2) symmetry of simultaneous spin and space rotations is broken into discrete cyclic groups, various types of lattice structures emerge in the absence of a lattice potential. Examples include two different kagome lattices for pseudo-spin-

\frac{1}{2}

condensates and a nematic vortex lattice in which uniaxial and biaxial spin textures align alternatively for spin-2 condensates. For the pseudo-spin-

\frac{1}{2}

system, although mean-field states always break time-reversal symmetry, there exists a time-reversal invariant many-body ground state, which is fragmented and expected to be observed in a microcondensate.