RQC Seminar
77th RQC Seminar
講演者
Prof. Mark Mitchison
( School of Physics,
Trinity College Dublin, Ireland )日程
2023年8月21日(月) 16:00-17:00
開催場所
ハイブリッド(ZOOM・ 研究本館3階 セミナー室(345-347) C01)
講演タイトル
Current fluctuations in continuously measured quantum systems: lessons from the critical Kerr model
お問合せ
rqc_info[at]ml.riken.jp
講演概要
Continuously measured quantum systems are characterized by an output current, in the form of a stochastic and correlated time series which conveys crucial information about the underlying quantum system. In this talk, I will present a theoretical framework to describe current fluctuations, which brings together concepts from continuous measurement theory and full counting statistics into a unified toolbox [1]. As an application, I will discuss current fluctuations in the parametrically pumped Kerr (PPK) model. The PPK model describes a driven-dissipative nonlinear cavity, whose nonequilibrium phase diagram features both continuous and discontinuous quantum phase transitions. When continuously measuring light leaking from the cavity, the photocurrent shows interesting divergences near criticality, whose nature depends both on the order of the phase transition and the choice of measurement basis [2]. These findings highlight the rich features of current fluctuations near nonequilibrium phase transitions in quantum-optical systems. Time permitting, I will also provide an outlook on some interesting future directions related to strongly coupled transport problems [3,4] and the thermodynamics of clocks [5,6].
[1] G. T. Landi, M. J. Kewming, M. T. Mitchison & P. P. Potts, arXiv:2303.04270
[2] M. J. Kewming, M. T. Mitchison & G. T. Landi, Phys. Rev. A 106, 033707 (2022)
[3] M. Brenes et al., Phys. Rev. X 10, 031040 (2020)
[4] A. M. Lacerda et al., Phys. Rev. B 107, 195117 (2023)
[5] P. Erker et al., Phys. Rev. X 7, 031022 (2017)
[6] O. Culhane et al., arXiv:2307.09122