TY  - JOUR
A1  - Bányai, Ladislaus Alexander
A1  - Bundaru, Mircea
A1  - Gartner, Paul
T1  - Thermal fluctuations and electromagnetic noise spectra in quantum statistical mechanics
T2  - International journal of theoretical physics
N2  - We derive the thermal noise spectrum of the longitudinal and transverse electric field operator of a given wave vector starting from the quantum-statistical definitions and relate it to the frequency and wave vector dependent complex conductivity in a homogeneous, isotropic system of electromagnetic interacting charged particles in the frame of the non-relativistic QED. No additional assumptions except the validity of linear response are used in the proof. The Nyquist formula for vanishing frequency, as well as the noise spectral density of Callen-Welton follow as byproduct. Furthermore we discuss also the noise of the photon occupation numbers.
KW  - Fluctuations
KW  - Noise spectra
KW  - Linear response
KW  - QED
KW  - Longitudinal and transverse electric fields
KW  - Nyquist noise
KW  - Photon number noise
Y1  - 2022
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/69490
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-694903
SN  - 1572-9575
N1  - Open Access funding enabled and organized by Projekt DEAL.
VL  - 61
IS  - 6, art. 164
SP  - 1
EP  - 14
PB  - Springer Science + Business Media B.V.
CY  - New York, NY
ER  -