Quantum-Heat Fluctuation Relations in Three-Level Systems Under Projective Measurements
We study the statistics of energy fluctuations in a three-level quantum system subject to a sequence of projective quantum measurements. We check that, as expected, the quantum Jarzynski equality holds provided that the initial state is thermal. The latter condition is trivially satisfied for two-le...
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| Published in | Condensed matter Vol. 5; no. 1; p. 17 |
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| Language | English |
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| Abstract | We study the statistics of energy fluctuations in a three-level quantum system subject to a sequence of projective quantum measurements. We check that, as expected, the quantum Jarzynski equality holds provided that the initial state is thermal. The latter condition is trivially satisfied for two-level systems, while this is generally no longer true for N-level systems, with N > 2 . Focusing on three-level systems, we discuss the occurrence of a unique energy scale factor β eff that formally plays the role of an effective inverse temperature in the Jarzynski equality. To this aim, we introduce a suitable parametrization of the initial state in terms of a thermal and a non-thermal component. We determine the value of β eff for a large number of measurements and study its dependence on the initial state. Our predictions could be checked experimentally in quantum optics. |
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| AbstractList | We study the statistics of energy fluctuations in a three-level quantum system subject to a sequence of projective quantum measurements. We check that, as expected, the quantum Jarzynski equality holds provided that the initial state is thermal. The latter condition is trivially satisfied for two-level systems, while this is generally no longer true for N-level systems, with N > 2. Focusing on three-level systems, we discuss the occurrence of a unique energy scale factor [[beta].sub.eff] that formally plays the role of an effective inverse temperature in the Jarzynski equality. To this aim, we introduce a suitable parametrization of the initial state in terms of a thermal and a non-thermal component. We determine the value of [[beta].sub.eff] for a large number of measurements and study its dependence on the initial state. Our predictions could be checked experimentally in quantum optics. Keywords: fluctuation theorems; nonequilibrium statistical mechanics; quantum thermodynamics We study the statistics of energy fluctuations in a three-level quantum system subject to a sequence of projective quantum measurements. We check that, as expected, the quantum Jarzynski equality holds provided that the initial state is thermal. The latter condition is trivially satisfied for two-level systems, while this is generally no longer true for N-level systems, with N > 2 . Focusing on three-level systems, we discuss the occurrence of a unique energy scale factor β eff that formally plays the role of an effective inverse temperature in the Jarzynski equality. To this aim, we introduce a suitable parametrization of the initial state in terms of a thermal and a non-thermal component. We determine the value of β eff for a large number of measurements and study its dependence on the initial state. Our predictions could be checked experimentally in quantum optics. |
| Audience | Academic |
| Author | Gherardini, Stefano Ruffo, Stefano Giachetti, Guido Trombettoni, Andrea |
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| SubjectTerms | Analysis fluctuation theorems Fluctuations (Physics) Forecasts and trends Heating Measurement nonequilibrium statistical mechanics Quantum mechanics quantum thermodynamics Statistical mechanics |
| Title | Quantum-Heat Fluctuation Relations in Three-Level Systems Under Projective Measurements |
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