The laws of physics are often expressed as limitations on what physical systems can and cannot do. This fundamental idea is at the core of Quantum Resource Theories, a rapidly evolving framework that postulates certain physical limitations on the evolution of quantum systems, and formally describes their consequences. The goal of this thesis is twofold. First, to use a resource-theoretic approach to better understand the role and significance of quantum effects in thermodynamic processes. Second, to utilise this approach in establishing a direct and operational interpretation of nonclassical effects encountered in quantum nonlocality. In the first part we investigate the resource theory of quantum thermodynamics. First, we report a surprising property of quantum catalysis: We present numerical results indicating that in quantum thermodynamics, contrary to the intuitive understanding of catalysis, any non-equilibrium quantum state, given sufficient dimension, acts as a catalyst for all possible transformations. This result can be naturally extended to several other quantum resources theories, including the resource theories of entanglement and coherence. Second, we address the problem of defining work in quantum thermodynamics. We show that when the work reservoir is explicitly modelled as a quantum system, the effects associated with its bounded spectrum are emergent in the work distribution. These consequences are then shown have implications for the form of the celebrated Jarzynski equality and the free energy formulation of the second law of thermodynamics. In the second part we provide an operational characterisation of certain nonlocal phenomena. First, we look at “nonclassical teleportation”, a recently introduced concept that can be though of as providing acomplete description of the standard teleportation protocol. We show that “nonclassical teleportation” generalizes standard teleportation in the sense that it is the resource responsible for teleporting quantum correlations, instead of quantum states. Second, we discuss “Buscemi nonlocality”, a concept that can be viewed as a generalization of Bell nonlocality. Notably, we demonstrate that "Buscemi nonlocality" is a resource that allows two distant parties to measure distributed quantum states in a way that could never be achieved using only classical resources.
|Date of Award||14 Jul 2021|
- The University of Bristol
|Supervisor||A J Short (Supervisor) & Paul Skrzypczyk (Supervisor)|