TY - JOUR

T1 - Cavityless self-organization of ultracold atoms due to the feedback-induced phase transition

AU - Ivanov, Denis A.

AU - Ivanova, Tatiana Yu

AU - Caballero-Benitez, Santiago F.

AU - Mekhov, Igor B.

N1 - Funding Information: The financial support is provided by RSF 17-19-01097-P (St. Petersburg State University, AMO physics approach), DGAPA-UNAM IN109619 and CONACYT-364 Mexico A1-S-30934 (Universidad Nacional Autónoma de México, CMT approach), and EPSRC EP/I004394/1. Publisher Copyright: © 2020, The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/6/29

Y1 - 2020/6/29

N2 - Feedback is a general idea of modifying system behavior depending on the measurement outcomes. It spreads from natural sciences, engineering, and artificial intelligence to contemporary classical and rock music. Recently, feedback has been suggested as a tool to induce phase transitions beyond the dissipative ones and tune their universality class. Here, we propose and theoretically investigate a system possessing such a feedback-induced phase transition. The system contains a Bose-Einstein condensate placed in an optical potential with the depth that is feedback-controlled according to the intensity of the Bragg-reflected probe light. We show that there is a critical value of the feedback gain where the uniform gas distribution loses its stability and the ordered periodic density distribution emerges. Due to the external feedback, the presence of a cavity is not necessary for this type of atomic self-organization. We analyze the dynamics after a sudden change of the feedback control parameter. The feedback time constant is shown to determine the relaxation above the critical point. We show as well that the control algorithm with the derivative of the measured signal dramatically decreases the transient time.

AB - Feedback is a general idea of modifying system behavior depending on the measurement outcomes. It spreads from natural sciences, engineering, and artificial intelligence to contemporary classical and rock music. Recently, feedback has been suggested as a tool to induce phase transitions beyond the dissipative ones and tune their universality class. Here, we propose and theoretically investigate a system possessing such a feedback-induced phase transition. The system contains a Bose-Einstein condensate placed in an optical potential with the depth that is feedback-controlled according to the intensity of the Bragg-reflected probe light. We show that there is a critical value of the feedback gain where the uniform gas distribution loses its stability and the ordered periodic density distribution emerges. Due to the external feedback, the presence of a cavity is not necessary for this type of atomic self-organization. We analyze the dynamics after a sudden change of the feedback control parameter. The feedback time constant is shown to determine the relaxation above the critical point. We show as well that the control algorithm with the derivative of the measured signal dramatically decreases the transient time.

KW - BOSE-EINSTEIN CONDENSATE

KW - LIGHT-SCATTERING

KW - QUANTUM

KW - GASES

UR - http://www.scopus.com/inward/record.url?scp=85087014149&partnerID=8YFLogxK

U2 - 10.1038/s41598-020-67280-3

DO - 10.1038/s41598-020-67280-3

M3 - Article

C2 - 32601416

AN - SCOPUS:85087014149

VL - 10

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 10550

ER -