Interferometric Order Parameter for Excited-State Quantum Phase Transitions in Bose-Einstein Condensates

authored by

Polina Feldmann, Carsten Klempt, Augusto Smerzi, Luis Santos, Manuel Gessner

Abstract

Excited-state quantum phase transitions extend the notion of quantum phase transitions beyond the ground state. They are characterized by closing energy gaps amid the spectrum. Identifying order parameters for excited-state quantum phase transitions poses, however, a major challenge. We introduce a topological order parameter that distinguishes excited-state phases in a large class of mean-field models and can be accessed by interferometry in current experiments with spinor Bose-Einstein condensates. Our work opens a way for the experimental characterization of excited-state quantum phases in atomic many-body systems.

Organisation(s)

Institute of Theoretical Physics
Institute of Quantum Optics
QuantumFrontiers
CRC 1227 Designed Quantum States of Matter (DQ-mat)

External Organisation(s)

University of Florence (UniFi)
College de France
DLR-Center for Lightweight Production Technology (ZLP)

Type

Article

Journal

Physical review letters

Volume

126

ISSN

0031-9007

Publication date

10.06.2021

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Physics and Astronomy(all)

Electronic version(s)

https://arxiv.org/abs/2011.02823 (Access: Open)
https://doi.org/10.1103/PhysRevLett.126.230602 (Access: Closed)