PhD student, ICTQT, UG - OPUS 21 Project led by M. Horodecki (# of pos: 2)

We are looking for two PhD students to work in the International Centre for Theory of Quantum Technologies (ICTQT), funded by the Foundation for Polish Science, and hosted by the University of Gdańsk (UG) - pioneering and leading center of quantum information research in Poland.

ICTQT aim is to find new solutions and protocols for basic aspects of fundamental quantum physics, from new non-classical phenomena, measures of non-classicality, structural aspects of quantum theory, theory of quantum measurement, up to theory of open systems and quantum thermodynamics, and bring them into quantum technologies.

The ICTQT activity is focused on the scientific research in quantum foundations, quantum communication, quantum information, and development of quantum technologies with an emphasis on quantum communication and new computing techniques.

The Centre consists of 6 groups: Multiphoton Quantum Optics for Quantum Information (leader Marek Żukowski); New Quantum Resources (leader Paweł Horodecki); Foundational Underpinnings of Quantum Technologies (leader Ana Belen Sainz); New Quantum Resources and Thermodynamics (leader Michał Horodecki); Quantum Cybersecurity and Communication (leader Marcin Pawłowski); Quantum Open Systems in Relation to Quantum Optics (leader Łukasz Rudnicki).

More about the research groups please find at you will find here: https://ictqt.ug.edu.pl/

About the OPUS 21 project

The project aims at developing dynamical and kinematic approach to quantum thermal machines. In dynamical approach, evolution is described by Hamiltonian (or derived from it evolution equations) while in kinematic approach the processes are described by discrete unitary transformations, or completely positive maps executed by external agent, belonging to a suitable (thermodynamically motivated) class. I.e. by kinematic approach we mean resource theoretic approach to quantum thermodynamics. The two approaches are complementary. The dynamical approach is close to the physical realm of quantum thermal machines, but often requires numerics, and usually does not allow for proving general statements – one has to usually confine to specific models. The kinematic approach – inheriting methods from quantum information - although often does not refer to common experimental situations, allows to obtain analytical results, especially concerning limitations as well as optimization over possible processes. Thus is it important to develop both approaches and possible interconnections. The main objectives will be contained in the following tasks: dynamics, kinematics and interconnections.

Dynamics. We plan to re-examine the present results on thermodynamics of microscopic systems in the weak coupling non-Markovian regime. Our main tool is newly developed weak coupling non-Markovian dynamical equation (regularized cumulant equation). In particular, we want to solve an open problem of a description of heat flow for two systems coupled to two baths, so that it is consistent with thermodynamics (e.g. reproducing the known truth that heat flows from the hot bath to cold bath) for full range of coupling between the systems. Our working hypothesis is that the regularized cumulant equation will properly describe the thermodynamics of such scenario. Another topic is to analyse two systems operating as a heat engine, again, for parameters, for which no description consistent with thermodynamics is known. One of basic challenges will be to find proper description of heat currents in the non-Markovian weak coupling regime.

Kinematics. We plan to develop understanding of thermodynamical processes within the resource-theoretic approach. This includes: the relations between fluctuations and dissipation in the second order asymptotic limit; the problem of definition of work for explicit work reservoir possessing ground state; the long standing unsolved problem of embezzling (related to Planck-Kelvin formulation of the Second Law). Selected working hypotheses are:

(i) the resource-theoretic fluctuation-dissipation relation identified recently by PI and coworkers holds for general states

(ii) for states of work reservoir flat enough far from ground state average energy change give appropriate description work; while this hypothesis is implicitly assumed, apart from initial study by PI and coworkers no quantitative results are known – our main task will be to provide ones

(iii) for suitable scaling of catalyst error, the catalytic processes with small error on catalyst, will obey near identical laws as without error on catalyst at all.

Interconnections. We plan to seek for a connection between resource theoretic and dynamical models of quantum thermal machines. This includes seeking for a mapping from discrete models of thermal machines to autonomous ones. We want also to seek for a connection between fluctuation-dissipation theorem in open systems and the resourcetheoretic fluctuation dissipation relations. We shall also aim at developing foundations for definition of work within resource-theoretic picture, and apply the results in dynamical picture.

Keywords: quantum thermodynamics, open systems, quantum heat engines, thermal operations, resource theory, quantum batteries.

If you would like any further details about the project, the advertised positions, or life in Gdańsk then please feel free to get in contact ([email protected] ) for a chat.

PhD students positions are offered by the International Centre for Theory of Quantum Technologies of the University of Gdansk within the implementation of the OPUS 21 project entitled “Quantum open systems and thermodynamical resource theory (Polish: Kwantowe układy otwarte i termodynamiczna teoria zasobów)”. The project is financed by the National Science Centre (NCN).

Key responsibilities include: