RQC Seminar
62nd RQC Seminar
講演者
Mr. Daniele Lamberto
( Università degli Studi di Messina, Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra (MIFT) )日程
2023年7月20日(木) 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
On the Impossibility of Superradiant Phase Transitions in Many-Dipole Cavity-QED Systems
お問合せ
rqc_info[at]ml.riken.jp
講演概要
The possibility of a phase transition between a normal and a photon condensate
state (also known as superradiant phase transitions, SPT) in light-matter
systems under (electric) dipolar interactions is the subject of much debate, due
to numerous apparently conflicting no-go and counter no-go theorems (see, e.g.,
[1, 2, 3, 4]). It is worth pointing out that the debate is limited to the case of
(electric) dipolar interactions and there is a general agreement on the possibility
that ground state superradiance can occur in the presence of magnetic interactions
[5, 6]. Recent no-go theorems have provided rather general demonstrations
that gauge invariance forbids any phase transition to a photon condensate state
when the cavity-photon mode is assumed to be spatially uniform in the region
where the dipoles are located [4, 7]. On the other hand, a number of papers
still support the existence of a SPT in many-dipole cavity-QED systems (e.g.,
[8, 9, 10]). I present a brief historical account of this long standing debate and
try to identify the origin of the fundamental errors determining the prediction
of the SPT in many-dipole systems.
References
[1] M. Bamba and T. Ogawa, Phys. Rev. A, vol. 90, p. 063825, Dec 2014.
[2] L. Garziano, A. Settineri, O. Di Stefano, S. Savasta, and F. Nori, Phys.
Rev. A, vol. 102, p. 023718, Aug 2020.
[3] J. M. Knight, Y. Aharonov, and G. T. C. Hsieh, Phys. Rev. A, vol. 17, pp.
1454–1462, Apr 1978.
[4] G. M. Andolina, F. M. D. Pellegrino, V. Giovannetti, A. H. MacDonald,
and M. Polini, Phys. Rev. B, vol. 100, p. 121109, Sep 2019.
[5] G. Andolina, F. Pellegrino, V. Giovannetti, A. MacDonald, and M. Polini,
Phys. Rev. B, vol. 102, p. 125137, Sep 2020.
[6] J. Rom´an-Roche, F. Luis, and D. Zueco, Phys. Rev. Lett., vol. 127, p.
167201, Oct 2021.
[7] G. Andolina, F. Pellegrino, A. Mercurio, O. Di Stefano, M. Polini, and
S. Savasta, The European Physical Journal Plus, vol. 137, p. 1, Dec 2022.
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