Michele Campisi

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Two fundamental ingredients play a decisive role in the foundation of fluctuation relations: the principle of microreversibility and the fact that thermal equilibrium is described by the Gibbs canonical ensemble. Building on these two pillars the reader is guided through a self-contained exposition of the theory and applications of quantum fluctuation(More)
Based on the observation that the thermodynamic equilibrium free energy of an open quantum system in contact with a thermal environment is the difference between the free energy of the total system and that of the bare environment, the validity of the Crooks theorem and of the Jarzynski equality is extended to open quantum systems. No restrictions on the(More)
We illustrate recent results concerning the validity of the work fluctuation theorem in open quantum systems (Campisi et al 2009 Phys. Rev. Lett. 102 210401), by applying them to a solvable model of an open quantum system. The central role played by the thermodynamic partition function of the open quantum system, a two-level fluctuator with a strong quantum(More)
A question that is currently highly debated is whether the microcanonical entropy should be expressed as the logarithm of the phase volume (volume entropy, also known as the Gibbs entropy) or as the logarithm of the density of states (surface entropy, also known as the Boltzmann entropy). Rather than postulating them and investigating the consequence of(More)
We derive the Boltzmann principle SB=kB ln W based on classical mechanical models of thermodynamics. The argument is based on the heat theorem and can be traced back to the second half of the 19th century in the works of Helmholtz and Boltzmann. Despite its simplicity, this argument has remained almost unknown. We present it in a contemporary,(More)
A logarithmic oscillator (in short, log-oscillator) behaves like an ideal thermostat because of its infinite heat capacity: When it weakly couples to another system, time averages of the system observables agree with ensemble averages from a Gibbs distribution with a temperature T that is given by the strength of the logarithmic potential. The resulting(More)
We study stochastic energetic exchanges in quantumheat engines. Due tomicroreversibility, these obey a fluctuation relation, called the heat enginefluctuation relation, which implies the Carnot bound: nomachine can have an efficiency greater thanCarnot’s efficiency. The stochastic thermodynamics of a quantumheat engine (including the joint statistics of(More)
The exactly solvable model of a one dimensional isotropic XY spin chain is employed to study the thermodynamics of open systems. For this purpose the chain is subdivided into two parts, one part is considered as the system while the rest as the environment or bath. The equilibrium properties of the system display several anomalous aspects such as negative(More)