Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ab-initio theory of quantum fluctuations and relaxation oscillations in
  multimode lasers   We present an \emph{ab-initio} semi-analytical solution for the noise
spectrum of complex-cavity micro-structured lasers, including central
Lorentzian peaks at the multimode lasing frequencies and additional sidepeaks
due to relaxation-oscillation (RO) dynamics. In~Ref.~1, we computed the
central-peak linewidths by solving generalized laser rate equations, which we
derived from the Maxwell--Bloch equations by invoking the
fluctuation--dissipation theorem to relate the noise correlations to the
steady-state lasing properties; Here, we generalize this approach and obtain
the entire laser spectrum, focusing on the RO sidepeaks. Our formulation treats
inhomogeneity, cavity openness, nonlinearity, and multimode effects accurately.
We find a number of new effects, including new multimode RO sidepeaks and three
generalized $\alpha$ factors. Last, we apply our formulas to compute the noise
spectrum of single- and multimode photonic-crystal lasers.

8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con