dorsal/arxiv
View SchemaPhotoemissive sources and quantum stochastic calculus
| Authors | Alberto Barchielli, Giancarlo Lupieri |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/9711050 |
| URL | https://arxiv.org/abs/quant-ph/9711050 |
| Journal | In R. Alicki, M. Bozejko, W. A. Majewski (eds.), Quantum Probability, (Polish Academy of Sciences, Inst. of Math., Warszawa, 1998) pp. 53-62. |
Abstract
Just at the beginning of quantum stochastic calculus Hudson and Parthasarathy proposed a quantum stochastic Schrodinger equation linked to dilations of quantum dynamical semigroups. Such an equation has found applications in physics, mainly in quantum optics, but not in its full generality. It has been used to give, at least approximately, the dynamics of photoemissive sources such as an atom absorbing and emitting light or matter in an optical cavity, which exchanges light with the surrounding free space. But in these cases the possibility of introducing the gauge (or number) process in the dynamical equation has not been considered. In this paper we show, in the case of the simplest photoemissive source, namely a two-level atom stimulated by a laser, how the full Hudson-Parthasarathy equation allows to describe in a consistent way not only absorption and emission, but also the elastic scattering of the light by the atom. Morever, we study the differential and total cross sections for the scattering of laser light by the atom, as a function of the frequency of the stimulating laser. The resulting line-shape is very interesting. Not only a Lorentzian shape is permitted, but the full variety of Fano profiles can be obtained. The dependence of the line shape on the intensity of the stimulating laser is computed; in particular, the resonance position turns out to be intensity dependent, a phenomenon known as lamp shift.
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"abstract": "Just at the beginning of quantum stochastic calculus Hudson and Parthasarathy\nproposed a quantum stochastic Schrodinger equation linked to dilations of\nquantum dynamical semigroups. Such an equation has found applications in\nphysics, mainly in quantum optics, but not in its full generality. It has been\nused to give, at least approximately, the dynamics of photoemissive sources\nsuch as an atom absorbing and emitting light or matter in an optical cavity,\nwhich exchanges light with the surrounding free space. But in these cases the\npossibility of introducing the gauge (or number) process in the dynamical\nequation has not been considered. In this paper we show, in the case of the\nsimplest photoemissive source, namely a two-level atom stimulated by a laser,\nhow the full Hudson-Parthasarathy equation allows to describe in a consistent\nway not only absorption and emission, but also the elastic scattering of the\nlight by the atom. Morever, we study the differential and total cross sections\nfor the scattering of laser light by the atom, as a function of the frequency\nof the stimulating laser. The resulting line-shape is very interesting. Not\nonly a Lorentzian shape is permitted, but the full variety of Fano profiles can\nbe obtained. The dependence of the line shape on the intensity of the\nstimulating laser is computed; in particular, the resonance position turns out\nto be intensity dependent, a phenomenon known as lamp shift.",
"arxiv_id": "quant-ph/9711050",
"authors": [
"Alberto Barchielli",
"Giancarlo Lupieri"
],
"categories": [
"quant-ph"
],
"journal_ref": "In R. Alicki, M. Bozejko, W. A. Majewski (eds.), Quantum\n Probability, (Polish Academy of Sciences, Inst. of Math., Warszawa, 1998) pp.\n 53-62.",
"title": "Photoemissive sources and quantum stochastic calculus",
"url": "https://arxiv.org/abs/quant-ph/9711050"
},
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