Reversing the flow of heat in system of initially correlated qubits

Abstract: The Second Law of Thermodynamics is considered to be one of the most fundamental and important laws of Physics. Both Clausius and Kelvin reformulated the Second Law as statements concerning the behaviour of two communicating systems, set to interact at different temperatures. The average positive entropy production of any process, described by the Second Law, is often understood as a "thermodynamic arrow of time" capable of discerning the direction in which physical events should arrange. By studying a microscopic system described by two initially correlated qubits, in this thesis we explore the phenomenon of reverse energy flow. Differently from an often standard uncorrelated case, the correlated one shows properties that seem to suggest that a further generalization of both Clausius and Kelvin's statements is needed