The Gas Liquid Transition of Excitons: from Bose glass to BEC

Seminar

QUEST Center event

Yes

Speaker

Israel Bar Joseph (Weizmann)

Date

13/12/2018 - 15:30 - 14:30Add to Calendar 2018-12-13 14:30:00 2018-12-13 15:30:00 The Gas Liquid Transition of Excitons: from Bose glass to BEC In this talk I shall review our work on the gas-liquid transition of 2D excitons in GaAs quantum wells. Below a critical temperature and above a critical density this system undergoes a phase transition to a liquid state. By employing a variety of optical spectroscopy tools we map the phase diagram of the system, and show that the liquid is a Bose Einstein condensate of dark excitons (exciton state which is not coupled to light). We find that the liquid phase is fragmented below Tc and the spatial fluctuations decay as the temperature is lowered, manifesting a continuous transition from a Bose glass to BEC. Nano (206), 9th floor Department of Physics physics.dept@mail.biu.ac.il Asia/Jerusalem public

Place

Nano (206), 9th floor

Abstract

In this talk I shall review our work on the gas-liquid transition of 2D excitons in GaAs quantum wells. Below a critical temperature and above a critical density this system undergoes a phase transition to a liquid state. By employing a variety of optical spectroscopy tools we map the phase diagram of the system, and show that the liquid is a Bose Einstein condensate of dark excitons (exciton state which is not coupled to light).

We find that the liquid phase is fragmented below Tc and the spatial fluctuations decay as the temperature is lowered, manifesting a continuous transition from a Bose glass to BEC.