Upcoming seminars

A geometric approach to quantum thermodynamics: from quantum fluctuations to optimal protocols

Seminar date and time: 
2019-12-17 12:00
Author: 
Martí Perarnau Llobet
Affiliation: 
Max-Planck-Institute of Quantum Optics, Garching

The average dissipation generated during a slow thermodynamic process can be characterised by introducing a metric on the space of Gibbs states, in such a way that minimally-dissipating protocols correspond to geodesic trajectories. Furthermore, the dissipation is proportional to the work fluctuations for classical systems (which follows from the fluctuation-dissipation relation (FDR)), so that minimising dissipation also minimises fluctuations. In this talk, I will explain how this geometric picture is modified in the quantum regime.

No-go theorems for quantum resource purification, with applications to quantum computation

Seminar date and time: 
2019-12-11 12:00
Author: 
Zi-Wen Liu
Affiliation: 
Perimeter Institute for Theoretical Physics

The field of quantum information takes a pragmatic approach to examining and utilizing quantum mechanics, seeking to obtain rigorous understandings of which information processing tasks can (e.g. quantum computing, communication) or cannot (e.g.

Location: 
Contact: 

Quantum Floquet theory: An introduction

Seminar date and time: 
2019-12-10 15:00
Author: 
Andreu Riera Campeny

Systems with time-dependent Hamiltonians are not constrained to energy conservation. Hence, the dynamics of driven physical systems can be significantly different to its static counterpart. Then, driven systems are a new platform where exciting phenomena can be discovered. However, analytical solutions of the dynamics of driven systems are extremely rare and it is typically difficult to gain intuition.

Thermodynamics of precision in quantum non-equilibrium steady states

Seminar date and time: 
2019-11-27 12:00
Author: 
Giacomo Guarnieri
Affiliation: 
Trinity College Dublin

We investigate the fundamental trade-off between current fluctuations and entropy production for systems in non-equilibrium steady states (NESS). We use the technique of non-equilibrium statistical operators of McLennan/Zubarev form and illustrate how the entropy production can be expressed as a quantum relative entropy. Furthermore, by exploiting the geometry of the manifold of NESS states, we use parameter estimation in order to bound the co-variance of the currents in the NESS by the entropy production.

Location: 
Contact: 

Thermodynamic Information in the Maxwell Demon

Seminar date and time: 
2019-11-13 12:00
Author: 
Felix Ritort
Affiliation: 
Universitat de Barcelona

“Take a single DNA molecule and pull from its extremities while recording the force-extension curve until it gets fully straightened”. This thought experiment, which was just a dream a few decades ago, has now become standard in many research labs worldwide. Force spectroscopy techniques (such as laser optical tweezers) are a fabulous tool for manipulating and monitoring the direct action of biological molecules at the individual level, as well as measuring forces in the piconewton range and energies of roughly equivalent to 1kT, the thermal energy unit.

Quantum stochastic processes: A complete theory for non-Markovian quantum phenomena

Seminar date and time: 
2019-11-04 12:00
Author: 
Kavan Modi
Affiliation: 
Monash University, Melbourne

In science, we often want to characterise dynamical processes to identify the underlying physics, predict the future states, or exercise control over the system. If the state of the system at any time depends only on the state of the system at the previous time-step and some predetermined rule then the dynamics are characterised with relative ease. For instance, the dynamics of quantum mechanical systems in isolation is described in this way. However, when a quantum system repeatedly interacts with an environment, the environment often ’remembers’ information about the system's past.

Pages

Campus d'excel·lència internacional U A B