Seminare der Theoretischen Physik

Seminarraum 3, A.03.101

Theoretisch-physikalisches Seminar - Dienstag

Andre Eckardt

TU Berlin

Controlling many-body quantum systems using driving and dissipation

In recent years, we have seen major progress in the non-equilibrium control of many-body quantum systems. One tool, which has been applied successfully, is Floquet engineering, i.e. the use of strong time-periodic driving for effectively changing the properties of the system. A prominent example is the realization of effective magnetic fields for charge neutral particles (like atoms in optical lattices or photons in superconducting circuits). Another approach is known as reservoir engineering. Here the system is coupled to a controlled environment, which is designed to either cool the system or to stabilize a non-equilibrium steady state of interest. I will report on recent work, where we combine both approaches in open Floquet systems. One motivation is to use dissipation in order to counteract unwanted heating as it necessarily occurs in Floquet engineered systems, e.g. for the preparation of Floquet engineered topological states of matter. Another motivation is the stabilization of non-equilibrium steady states. Here, I will in discuss ordering away from equilibrium, like driving-induced Bose-condensation.

Aktuelle Probleme der theoretischen Festkörperphysik (Forschungsseminar M.Phy.411)

Giovanna Morigi

Search as (quantum) selforganized process

Efficient retrieval of information is a core operation in the world wide web, is essential for the sustainance of living organism, and is a paradigm for optimization algorithms. Inspired by the food search dynamics of living organisms, we discuss a search on a graph with multiple constraints where the dynamics is a selforganized process resulting from the interplay of coherent dynamics and Gaussian noise. We show that Gaussian noise can be beneficial to the search dynamics leading to significantly faster convergence to the optimal solution. We then analyse how these concepts can be extended to quantum searches, cast in terms of spatial searches on a graph and discuss whether and when the efficiency of noise-assisted quantum searches can outperform the one of unitary protocols.

Institute for Theoretical Physics/SR 3 A03.101

Seminar Statistical Physics

Gabriel Knotz

ITP

tba

Kontakt: Peter Sollich

Seminarraum 3, A.03.101

Theoretisch-physikalisches Seminar - Dienstag

Jens Bardarson

KTH Stockholm

tba


	April 2025

Di	29.04.2025 Seminarraum 3, A.03.101 Theoretische Physik
14:15	Theoretisch-physikalisches Seminar - Dienstag Andre Eckardt TU Berlin Controlling many-body quantum systems using driving and dissipation Abstract In recent years, we have seen major progress in the non-equilibrium control of many-body quantum systems. One tool, which has been applied successfully, is Floquet engineering, i.e. the use of strong time-periodic driving for effectively changing the properties of the system. A prominent example is the realization of effective magnetic fields for charge neutral particles (like atoms in optical lattices or photons in superconducting circuits). Another approach is known as reservoir engineering. Here the system is coupled to a controlled environment, which is designed to either cool the system or to stabilize a non-equilibrium steady state of interest. I will report on recent work, where we combine both approaches in open Floquet systems. One motivation is to use dissipation in order to counteract unwanted heating as it necessarily occurs in Floquet engineered systems, e.g. for the preparation of Floquet engineered topological states of matter. Another motivation is the stabilization of non-equilibrium steady states. Here, I will in discuss ordering away from equilibrium, like driving-induced Bose-condensation. Kontakt: Theoretische Physik


	Mai 2025

Mi	07.05.2025 SR4, A.04.101 Theoretische Physik
11:00	Aktuelle Probleme der theoretischen Festkörperphysik (Forschungsseminar M.Phy.411) Giovanna Morigi Search as (quantum) selforganized process Abstract Efficient retrieval of information is a core operation in the world wide web, is essential for the sustainance of living organism, and is a paradigm for optimization algorithms. Inspired by the food search dynamics of living organisms, we discuss a search on a graph with multiple constraints where the dynamics is a selforganized process resulting from the interplay of coherent dynamics and Gaussian noise. We show that Gaussian noise can be beneficial to the search dynamics leading to significantly faster convergence to the optimal solution. We then analyse how these concepts can be extended to quantum searches, cast in terms of spatial searches on a graph and discuss whether and when the efficiency of noise-assisted quantum searches can outperform the one of unitary protocols. Kontakt: Fabian Heidrich-Meisner

Do	08.05.2025 Institute for Theoretical Physics/SR 3 A03.101 Theoretische Physik
14:15	Seminar Statistical Physics Gabriel Knotz ITP tba Kontakt: Peter Sollich


	Juni 2025

Di	24.06.2025 Seminarraum 3, A.03.101 Theoretische Physik
14:15	Theoretisch-physikalisches Seminar - Dienstag Jens Bardarson KTH Stockholm tba Abstract tba Kontakt: Theoretische Physik