BEGIN:VCALENDAR VERSION:2.0 PRODID:Icfo X-PUBLISHED-TTL:P1W BEGIN:VEVENT UID:69d25621ee190 DTSTART:20230728T080000Z SEQUENCE:0 TRANSP:OPAQUE LOCATION:Auditorium SUMMARY:ICFO | MOHIT LAL BERA CLASS:PUBLIC DESCRIPTION:In this thesis\, our main objective is to utilize different kin ds of quantum dynamics \; as resources. To do so\, we investigate ther modynamics\, non-equilibrium steady states\, and dynamical spectroscopy in order to categorize the dynamics of quantum systems as having either no e xternal drive (self-drive)\, a weak external drive\, or a strong external drive\, respectively.In the first part\, we explore the dynamics of quantu m heat engines. In that\, we consider dynamics that are driven by time-ind ep-\\\\endent Hamiltonian\, i.e.\, without external driving. We show that when a working system non-locally interacts with two baths at different te mperatures\, the engine can operate in a one-step cycle\, yielding Carnot efficiency at maximum power. This advantage is exclusively because non-loc al operations are more powerful than local ones. To study such engines in a more systematic manner\, we develop a resource theory of heat engines. T his provides a framework to study quantum engines operating with a working system composed of a finite number of quantum particles and restricted to few observations\, i.e.\, in the one-shot finite-size regime. We also pro pose an experimentally feasible model of an engine using an atom-cavity sy stem that yields Carnot efficiency at maximum power. In the second part\, we consider open quantum dynamics\, where a system weakly interacts with e nvironments. In particular\, we study the Lindblad master equation-based d ynamics of quantum systems weakly coupled to two thermal baths at differen t temperatures. In general\, these dynamics lead to non-equilibrium steady states. By selectively coupling a quantum system to two different thermal baths\, a synthetic thermal bath can be engineered\, and the temperature of such a synthetic bath can be made negative. With this\, we \; explo re steady-state quantum thermodynamics with negative temperatures. We show that the zeroth and the Clausius state of the second law remain unaltered in the case of baths with negative temperatures. However\, the Kelvin-Pla nck statement of the second law updates in this case to incorporate the fo llowing. (i) There is spontaneous heat flow from a bath with a negative te mperature to a bath with a positive temperature. In this sense\, the baths with a negative temperature are `hotter' than the ones with a positive te mperature. (ii) There is spontaneous heat flow from a bath with a less neg ative temperature to a bath with a more negative temperature. We also intr oduce a continuous heat engine operating between a positive and negative t emperature bath. Our analysis shows that the heat-to-work conversion effic iency for such an engine is always unity. We study the thermodynamic impli cations of our results. The third part of the thesis explores systems driv en by strong external fields. In such circumstances\, we encounter transie nt quantum dynamics\, which cannot be described by thermodynamics. This ki nd of dynamics is utilized for dynamical spectroscopy. Particularly\, we h ave studied high harmonic generation where a strong laser field interacts with matter. By utilizing the high harmonic generation \; mechanism\, we characterize the topological features of solids.\nThesis Director: Prof Dr. Maciej Lewenstein DTSTAMP:20260405T123129Z END:VEVENT END:VCALENDAR