Novel phases in rotating Bose condensed gas: vortices and quantum correlation

Abstract

We present the exact diagonalization study of rotating Bose-condensed gas interacting via finiterange Gaussian potential confined in a quasi-2D harmonic trap. The system Hamiltonian matrix is diagonalized in given subspaces of quantized total angular momentum to obtain the lowest-energy eigenstate employing the beyond lowest-Landau-level approximation. In the co-rotating frame, the quantum mechanical stability of angular momentum states is discussed for the existence of phase transition between the stable states. Thereby analyzing the von Neumann entanglement entropy and degree of condensation provide the information about quantum phase correlation in the many-body states. Calculating the conditional probability distribution, we further probe the internal structure of quantum mechanically stable and unstable states. Much emphasis is put on finding the spatial correlation of bosonic atoms in the rotating system for the formation and entry of singly quantized vortices, and then shaping into canonical polygons with and without a central vortex at the trap center. The results are summarized in the form of a movie depicting the vortex patterns having discrete p-fold rotational symmetry with p = 2, 3, 4, 5, 6.

A Scaling Function for the Particle Entanglement Entropy of Fermions

“…In one spatial dimension (1D) this particle entanglement entropy S(n) can be sensitive to interactions, phase transitions [5,6], and particle statistics at leading order. It has been used to probe quantum Hall states [7][8][9][10][11][12] as well as systems of non-interacting [13], and interacting bosons [14][15][16][17][18], fermions [19][20][21][22], and anyons [23].…”

A scaling function for the particle entanglement entropy of fermions

“…In one spatial dimension (1D), the particle entanglement entropy S (n) can be sensitive to interactions, phase transitions [6,7], and particle statistics at the leading order. It has been used to probe the quantum Hall states [8][9][10][11][12][13], systems of non-interacting [14] and interacting bosons [15][16][17][18][19], fermions [20][21][22][23], and anyons [24].…”