The existence of the third cumulant S3 of voltage ﬂuctuations has demonstrated the non-Gaussian aspect of shot noise in electronic transport. Until now, measurements have been performed at low frequency, i.e. in the classical regime 1ω
1. The electromagnetic environment of the sample has been proven to strongly inﬂuence the measure¬ment, through the possible modulation of the noise of the sample. What happens to this mechanism in the quantum regime ?
2. For eV < 1ω, the noise is due to zero point ﬂuctuations and keeps its equilibrium value : S2 = G1ω with G the conductance of the sample. Therefore, S2 is independent of the bias voltage and no photon is emitted by the conductor. It is possible, as suggested by some theories [1, 2], that S3 =0 in this regime ?
With regard to these questions, we give theoretical and experimental answers to the environmental effects showing they involve dynamics of the quantum noise. Using these results, we investigate the question of the third cumulant of quantum noise in the a tunnel junction.
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 J. Salo, F. W. J. Hekking, and J. P. Pekola , Frequency-dependent current correlation functions from scattering theory, Phys. Rev. B 74 pp. 125427 (2006)