Quantum statistical theory of the ring laser

Journal Article · Sun Feb 01 04:00:00 EST 1981 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.23.837· OSTI ID:6933283

Singh, S

A unified quantum treatment is presented for bidirectional two-mode ring lasers using the approach of Haken and co-workers. Equations of motion for the reduced density matrix of the field have been derived and used to study the fluctuation properties of the radiation field in different kinds of active media. The steady-state photon number distribution for an inhomogeneously broadened gas ring laser is derived. It is shown that for equal losses the relative fluctuations and normalized cross correlation of the photon numbers approach values 1/3 and -1/3, respectively, for large excitations. For unequal losses the laser may emit typical single-mode laser radiation in the direction of the favored mode and typical equilibrium blackbody radiation in the direction of the weaker mode. Our results generally agree with the predictions of earlier treatments when the losses are equal. However, for unequal losses we predict different behavior for large excitations. Effects of detuning, spatial, and temporal variation of atomic inversion on the fluctuation properties have been investigated in the coherent-state diagonal representation of the density matrix, and steady-state intensity distributions have been derived for various kinds of active atoms. It is shown that for inhomogeneously broadened solid-state ring lasers spatial inhomogeneities may couple the modes strongly and the statistical properties of such lasers, characterized by a double-peaked intensity distribution and large relative-intensity fluctuations, may be similar to those of a homogeneously broadened ring laser. Curves are presented to illustrate the behavior.

• Research Organization: Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627
• OSTI ID: 6933283
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 23:2; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
DENSITY MATRIX
DIFFERENTIAL EQUATIONS
ELECTROMAGNETIC RADIATION
EQUATIONS
EQUATIONS OF MOTION
FLUCTUATIONS
LASER RADIATION
LASERS
MATRICES
OSCILLATION MODES
PARTIAL DIFFERENTIAL EQUATIONS
RADIATIONS
SOLID STATE LASERS
VARIATIONS