Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Semi-classical theory of quiet lasers. I: Principles   When light originating from a laser diode driven by non-fluctuating
electrical currents is incident on a photo-detector, the photo-current does not
fluctuate much. Precisely, this means that the variance of the number of
photo-electrons counted over a large time interval is much smaller that the
average number of photo-electrons. At non-zero Fourier frequency $\Omega$ the
photo-current power spectrum is of the form $\Omega^2/(1+\Omega^2)$ and thus
vanishes as $\Omega\to 0$, a conclusion equivalent to the one given above. The
purpose of this paper is to show that results such as the one just cited may be
derived from a (semi-classical) theory in which neither the optical field nor
the electron wave-function are quantized. We first observe that almost any
medium may be described by a circuit and distinguish (possibly non-linear)
conservative elements such as pure capacitances, and conductances that
represent the atom-field coupling. The theory rests on the non-relativistic
approximation. Nyquist noise sources (in which the Planck term $\hbar\omega/2$
is being restored) are associated with positive or negative conductances, and
the law of average-energy conservation is enforced. We consider mainly
second-order correlations in stationary linearized regimes.

33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int