Joint ICTP/SISSA Condensed Matter Seminar, 11 July at 11:00 by Marzena H. Szymanska

[CMSP Seminars Secretariat]

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  Joint ICTP/SISSA Condensed Matter Seminar
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** * * Tuesday**, 11 July 2023, 11:00**am ***(CET)** * **
In person: *Luigi Stasi Seminar Room **(Leonardo Building, second floor)***
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/Zoom: 
https://zoom.us/meeting/register/tJ0tdu2tpz0oH9Tkny22wffqEBd_F7cBVTOJ/<https://zoom.us/meeting/register/tJIsfuuhqjsrE9EZY2loNxNobg8Lf39NUVHJ>

Speaker: *Marzena H. Szymanska *(University College London)

Title: *Novel Non-equilibrium Phenomena in Quantum Fluids of Light*

Abstract:

Driven-dissipative quantum fluids of light, experimentally realised in 
for example semiconductor microcavities, circuit or cavity QED systems, 
provide a unique testbed to explore new non-equilibrium quantum 
phenomena. I will review recent progress in this field. In particular, 
we show that polariton quantum fluid can exhibit a non-equilibrium 
order, where superfluidity is accompanied by stretched exponential decay 
of correlations [1]. This celebrated Kardar-Parisi-Zhang (KPZ) phase has 
not been achieved before in any system in 2D, and even 1D realisations 
have not been conclusive. I will then discuss how these systems can 
undergo other unconventional phase transitions and orders [2], and 
display flow properties connected but distinct from conventional 
superfluidity. Finally, when placed in strained honeycomb lattice 
potentials, polariton fluids can condense into a rotating state, the 
lowest Landau level, forming a vortex array and spontaneously breaking 
time reversal symmetry [3]. Describing strong quantum correlations in 
open systems with drive and dissipation, especially in two dimensions, 
is a numerical challenge. I will briefly present our attempts at 
developing suitable methods, based on stochastic and tensor network 
approaches [4].

[1] A. Zamora et al, PRX 7, 041006 (2017); PRL 125, 265701 (2020); A. 
Ferrier et al, PRB 105, 205301 (2022)

[2] G. Dagvadorj et al, PRL 130, 136001 (2023); PRB 104, 165301 (2021)

[3] C. Lledo et al, SciPost 12, 068 (2022)

[4] C. Mc Keever et al, PRX 11, 021035 (2021); P. Deuar et al, PRX 
Quantum, 2, 010319 (2021)