Title: Dissipative Phase Transition in the Quantum Rabi Model with a Structured Environment
Speaker: Mark Mitchison (Trinity College Dublin)
Abstract: I will introduce the super-radiantquantum phase transition in the Rabi model and its dissipative generalisation [1,2]. I will then extend the model to include both a structured bath (i.e. frequency-dependent noise) and pure white noise. The frequency dependence of the noise is found to strongly modify the critical exponents and the dynamics of the system close to criticality. Remarkably, in the sub-Ohmic regime an unconventional second-order phase transition arises, in which the soft-mode frequency and decay rate remain finite across the critical point. This strongly suppresses the critical exponent describing the behaviour of fluctuations close to the transition. I will describe how these unusual effects compete with standard features of second-order quantum criticality induced by white noise and/or finite temperature.
Time: Thursday, 12 September 2019, 2:30pm
Location: Lecture Room, 1st Floor, School of Theoretical Physics, DIAS,
10 Burlington Road, Dublin 4
Leave a Comment
Posted: 9th September 2019 by George Rogers
Thursday 12th September : Dissipative Phase Transition in the Quantum Rabi Model with a Structured Environment
Title: Dissipative Phase Transition in the Quantum Rabi Model with a Structured Environment
Speaker: Mark Mitchison (Trinity College Dublin)
Abstract: I will introduce the super-radiantquantum phase transition in the Rabi model and its dissipative generalisation [1,2]. I will then extend the model to include both a structured bath (i.e. frequency-dependent noise) and pure white noise. The frequency dependence of the noise is found to strongly modify the critical exponents and the dynamics of the system close to criticality. Remarkably, in the sub-Ohmic regime an unconventional second-order phase transition arises, in which the soft-mode frequency and decay rate remain finite across the critical point. This strongly suppresses the critical exponent describing the behaviour of fluctuations close to the transition. I will describe how these unusual effects compete with standard features of second-order quantum criticality induced by white noise and/or finite temperature.
Time: Thursday, 12 September 2019, 2:30pm
Location: Lecture Room, 1st Floor, School of Theoretical Physics, DIAS,
10 Burlington Road, Dublin 4
Category: Regular seminars, School of Theoretical Physics News & Events
Recent Posts
Internationally acclaimed scientific integrity expert Elisabeth Bik to deliver DIAS Day Lecture
Earth Day 2022: DIAS Contributing to the sustainability of our world
DIAS Cosmic Physics marks 75 years of ground-breaking discoveries about our planet and universe
In a world first, Irish scientists observe cosmic explosion with unprecedented detail
DIAS celebrates success of female researchers for International Women’s Day 2022
Language switcher
Tweets by DIAS_Dublin