Quantum thermodynamics in chiral two--level systems. The quantum stochastic resonance

A Langevin canonical framework for a chiral two-level system coupled to a bath of harmonic oscillators is used within a coupling scheme different from the well-known spin-boson model. From this stochastic dynamics, within the Markovian regime and Ohmic friction, some standard quantum thermodynamics functions such as the energy average and heat capacity can be extracted. In particular, special emphasis is put on the so-called quantum stochastic resonance which is a cooperative effect of friction, noise and periodic driving occurring in a bistable system.