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Title: Spin dynamics of large-spin fermions in a harmonic trap

Abstract

Understanding the collective dynamics in a many-body system has been a central task in condensed matter physics. To achieve this task, we develop a Hartree–Fock theory to study the collective oscillations of spinor Fermi system, motivated by recent experiment on spin-9/2 fermions. We observe an oscillation period shoulder for small rotation angles. Different from previous studies, where the shoulder is found connected to the resonance from periodic to running phase, here the system is always in a running phase in the two-body phase space. This shoulder survives even in the many-body oscillations, which could be tested in the experiments. We also show how these collective oscillations evolve from two- to many-body. Our theory provides an alternative way to understand the collective dynamics in large-spin Fermi systems.

Authors:
; ;
Publication Date:
OSTI Identifier:
22617495
Resource Type:
Journal Article
Resource Relation:
Journal Name: Annals of Physics; Journal Volume: 379; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; FERMI GAS; FERMIONS; HARMONICS; HARTREE-FOCK METHOD; PHASE SPACE; SPIN; SPINORS

Citation Formats

Xu, Junjun, Feng, Tongtong, and Gu, Qiang, E-mail: qgu@ustb.edu.cn. Spin dynamics of large-spin fermions in a harmonic trap. United States: N. p., 2017. Web. doi:10.1016/J.AOP.2017.02.003.
Xu, Junjun, Feng, Tongtong, & Gu, Qiang, E-mail: qgu@ustb.edu.cn. Spin dynamics of large-spin fermions in a harmonic trap. United States. doi:10.1016/J.AOP.2017.02.003.
Xu, Junjun, Feng, Tongtong, and Gu, Qiang, E-mail: qgu@ustb.edu.cn. Sat . "Spin dynamics of large-spin fermions in a harmonic trap". United States. doi:10.1016/J.AOP.2017.02.003.
@article{osti_22617495,
title = {Spin dynamics of large-spin fermions in a harmonic trap},
author = {Xu, Junjun and Feng, Tongtong and Gu, Qiang, E-mail: qgu@ustb.edu.cn},
abstractNote = {Understanding the collective dynamics in a many-body system has been a central task in condensed matter physics. To achieve this task, we develop a Hartree–Fock theory to study the collective oscillations of spinor Fermi system, motivated by recent experiment on spin-9/2 fermions. We observe an oscillation period shoulder for small rotation angles. Different from previous studies, where the shoulder is found connected to the resonance from periodic to running phase, here the system is always in a running phase in the two-body phase space. This shoulder survives even in the many-body oscillations, which could be tested in the experiments. We also show how these collective oscillations evolve from two- to many-body. Our theory provides an alternative way to understand the collective dynamics in large-spin Fermi systems.},
doi = {10.1016/J.AOP.2017.02.003},
journal = {Annals of Physics},
number = ,
volume = 379,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2017},
month = {Sat Apr 15 00:00:00 EDT 2017}
}
  • We study an atomic Fermi gas interacting through repulsive contact forces in a one-dimensional harmonic trap. Bethe-ansatz solutions lead to an inhomogeneous Tomonaga-Luttinger model for the low energy excitations. The equations of motion for charge and spin density waves are analyzed both near the trap center and near the trap edges. While the center shows conventional spin-charge separation, the edges cause a giant increase of the separation between these modes.
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