Collective excitations in cigar-shaped spin-orbit-coupled spin-1 Bose-Einstein condensates

Year: 2022

Authors: Rajat, Roy A., Gautam S.

Autors Affiliation: Department of Physics, Indian Institute of Technology Ropar, Punjab, Rupnagar, 140001, India; INO-CNR Bec Center and Universita di Trento, Via Sommarive 14, Trento, 38123, Italy; School of Basic Sciences, Indian Institute of Technology Mandi, Himachal Pradesh, Mandi, 175075, India

Abstract: We study theoretically the collective excitations of a spin-orbit-coupled spin-1 Bose-Einstein condensate with antiferromagnetic spin-exchange interactions in a cigar-shaped trapping potential at zero and finite temperatures using the Hartree-Fock-Bogoliubov theory with Popov approximation. The collective modes at zero temperature are corroborated by real-Time evolution of the ground state subjected to a perturbation suitable to excite a density or a spin mode. We also calculate a few low-lying modes analytically and find very good agreement with the numerical results. We confirm the presence of excitations belonging to two broad categories, namely, density and spin excitations, based on the calculation of dispersion. The degeneracy between a pair of spin modes is broken by the spin-orbit coupling. At finite temperature, spin and density excitations show qualitatively different behavior as a function of temperature.

Journal/Review: PHYSICAL REVIEW A

Volume: 106 (1)      Pages from: 013304-1  to: 013304-12

More Information: S.G. acknowledges support from the Science and Engineering Research Board, Department of Science and Technology, Government of India through Projects No. ECR/2017/001436 and No. CRG/2021/002597.
KeyWords: ENERGY; GASES
DOI: 10.1103/PhysRevA.106.013304