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arXiv · 1001.4389

Nonzero temperature effects on antibunched photons emitted by a quantum point contact out of equilibrium

I. C. Fulga·F. Hassler·C. W. J. Beenakker
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Abstract

Electrical current fluctuations in a single-channel quantum point contact can produce photons (at frequency omega close to the applied voltage V x e/hbar) which inherit the sub-Poissonian statistics of the electrons. We extend the existing zero-temperature theory of the photostatistics to nonzero temperature T. The Fano factor F (the ratio of the variance and the average photocount) is <1 for T 1 for T>T_c (bunched photons). The crossover temperature T_c ~ Deltaomega x hbar/k_B is set by the band width Deltaomega of the detector, even if hbar x Deltaomega << eV. This implies that narrow-band detection of photon antibunching is hindered by thermal fluctuations even in the low-temperature regime where thermal electron noise is negligible relative to shot noise.

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I. C. Fulga, F. Hassler, C. W. J. Beenakker. 2010-01-25. Nonzero temperature effects on antibunched photons emitted by a quantum point contact out of equilibrium. https://doi.org/10.1103/physrevb.81.115331

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