dorsal/arxiv
View SchemaA modern review of the two-level approximation
| Authors | Marco Frasca |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0209056 |
| URL | https://arxiv.org/abs/quant-ph/0209056 |
| DOI | 10.1016/S0003-4916(03)00078-2 |
| Journal | Annals of Physics 306, 193-208 (2003) |
Abstract
The paradigm of the two-level atom is revisited and its perturbative analysis is discussed in view of the principle of duality in perturbation theory. The models we consider are a two-level atom and an ensemble of two-level atoms both interacting with a single radiation mode. The aim is to see how the latter can be actually used as an amplifier of quantum fluctuations to the classical level through the thermodynamic limit of a very large ensemble of two-level atoms [M. Frasca, Phys. Lett. A {\bf 283}, 271 (2001)] and how can remove Schr\"odinger cat states. The thermodynamic limit can be very effective for producing both classical states and decoherence on a quantum system that evolves without dissipation. Decoherence without dissipation is indeed an effect of a single two-level atom interacting with an ensemble of two-level atoms, a situation that proves to be useful to understand recent experiments on nanoscale devices showing unexpected disappearance of quantum coherence at very low temperatures.
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"abstract": "The paradigm of the two-level atom is revisited and its perturbative analysis\nis discussed in view of the principle of duality in perturbation theory. The\nmodels we consider are a two-level atom and an ensemble of two-level atoms both\ninteracting with a single radiation mode. The aim is to see how the latter can\nbe actually used as an amplifier of quantum fluctuations to the classical level\nthrough the thermodynamic limit of a very large ensemble of two-level atoms [M.\nFrasca, Phys. Lett. A {\\bf 283}, 271 (2001)] and how can remove Schr\\\"odinger\ncat states. The thermodynamic limit can be very effective for producing both\nclassical states and decoherence on a quantum system that evolves without\ndissipation. Decoherence without dissipation is indeed an effect of a single\ntwo-level atom interacting with an ensemble of two-level atoms, a situation\nthat proves to be useful to understand recent experiments on nanoscale devices\nshowing unexpected disappearance of quantum coherence at very low temperatures.",
"arxiv_id": "quant-ph/0209056",
"authors": [
"Marco Frasca"
],
"categories": [
"quant-ph",
"cond-mat.mes-hall",
"math-ph",
"math.MP",
"physics.atom-ph"
],
"doi": "10.1016/S0003-4916(03)00078-2",
"journal_ref": "Annals of Physics 306, 193-208 (2003)",
"title": "A modern review of the two-level approximation",
"url": "https://arxiv.org/abs/quant-ph/0209056"
},
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