Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Theory of a two-photon squeezed laserlike oscillator

Rupamanjari Ghosh, G. S. Agarwal

Published Feb 1, 1989• 14 citations
Publisher

Abstract

It is theoretically shown how a two-photon laserlike oscillator with strongly squeezed output can be constructed. The physical mechanism leading to squeezed laserlike oscillator is the strong competition among the nonlinear gain due to resonant four-wave mixing process, nonlinear losses due to the absorption of generated photons, and linear losses from the cavity. In the balanced case, the photon correlations result in a linewidth that is narrower than the Schawlow-Townes limit.

DOI
10.1103/physreva.39.1582

Related papers

Two-photon squeezed laser with long-lived atoms

Ashish Agarwal, Rupamanjari Ghosh

We present the quantum theory of a two-photon nonlinear laser when the lasing medium consists of long-lived atoms. There is no population inversion in this laser, but the system exhibits gain arising from the four-wave-mixing process in an active nonlinear medium. The strong phase correlation between the photons generated in four-wave mixing leads to a narrower than usual linewidth of the two-photon laser far above threshold. The laser output is also squeezed. Systems with a higher lifetime have the advantage of requiring a lower pump to reach the threshold of laser oscillation. We give explicit solutions for the noise spectrum of the intensity difference of the two output modes in the steady state and show that it is highly squeezed even for non-Markov systems.

Physical Review A•Aug 1, 1994•8 citations

Generation of squeezing in two-photon three-level media

Sunghyuck An, Murray Sargent

We present a fully quantum-mechanical theory of nondegenerate four-wave mixing processes in three-level cascades with a two-photon pump. The results are applied to the generation of squeezed states of light. We find almost perfect squeezing for some strong pump intensities and tunings within the Rabi sidebands. We find good broadband squeezing for low pump intensities and tunings outside a small region around central tuning. Both cases avoid regions of significant spontaneous emission.

Optics Letters•Jun 1, 1988•10 citations

Theory of Linewidth Squeezing in an Optical Parametric Oscillator

Yun Zhao, Alexander L. Gaeta

We develop a quantum stochastic model for optical parametric oscillators (OPOs) coupled to a two-mode-squeezed reservoir state and show that this configuration can significantly squeeze the linewidth of the OPO below the Schawlow-Townes linewidth.

•Jan 1, 2025•0 citations

Generation of Squeezed States by Four-Wave-Mixing in a Cavity

R. E. Slusher, Bernard Yurke, Leo W. Hollberg +1 more

Phase dependent nonlinear optical processes can make large fractional changes in the phase and amplitude of an optical field. An example is the prediction(1) that four-wave-mixing can generate squeezed states of an optical field where the variance in the two quadratures of the field are unequal. In order to observe squeezed states and utilize them in interferometric measurements this inequality in variances must be large (e.g. ≳ 50%). The large phase shifts required to achieve this regime of squeezing can be obtained near the threshold for oscillation of four-wave-mixing in an optical cavity. (2) This paper describes an experimental study(3) of four-wave-mixing in a cavity near threshold using the nonlinear index of the Na atomic resonance.

International Meeting on Instabilities and Dynamics of Lasers and Nonlinear Optical Systems•Jan 1, 1985•0 citations

Generation of Pair Coherent States and Squeezing via the Competition of Four-Wave Mixing and Amplified Spontaneous Emission

G. S. Agarwal

Strong competition between four-wave mixing and amplified spontaneous emission in resonant two-photon excitations is shown to generate radiation fields with strong squeezing and antibunching. The generated fields are in a new type of coherent state which is an eigenstate of the operator corresponding to the simultaneous annihilation of photons in two modes.

Physical Review Letters•Aug 18, 1986•242 citations

Two-photon Absorption of Squeezed Light in the Continuous-Wave Limit

Christian Drago, John E. Sipe

We calculate the two-photon absorption for squeezed light pumped by a continuous-wave source, near or far from resonance, beyond the low intensity limit. For typical two-photon absorption parameters, we find no squeezed light enhancement.

Conference on Lasers and Electro-Optics•Jan 1, 2022•0 citations
It is theoretically shown how a two-photon laserlike oscillator with strongly squeezed output can be constructed. The physical mechanism leading to squeezed laserlike oscillator is the strong competition among the nonlinear gain due to resonant four-wave mixing process, nonlinear losses due to the absorption of generated photons, and linear losses from the cavity. In the balanced case, the photon correlations result in a linewidth that is narrower than the Schawlow-Townes limit.
We present the quantum theory of a two-photon nonlinear laser when the lasing medium consists of long-lived atoms. There is no population inversion in this laser, but the system exhibits gain arising from the four-wave-mixing process in an active nonlinear medium. The strong phase correlation between the photons generated in four-wave mixing leads to a narrower than usual linewidth of the two-photon laser far above threshold. The laser output is also squeezed. Systems with a higher lifetime have the advantage of requiring a lower pump to reach the threshold of laser oscillation. We give explicit solutions for the noise spectrum of the intensity difference of the two output modes in the steady state and show that it is highly squeezed even for non-Markov systems.
Phase dependent nonlinear optical processes can make large fractional changes in the phase and amplitude of an optical field. An example is the prediction(1) that four-wave-mixing can generate squeezed states of an optical field where the variance in the two quadratures of the field are unequal. In order to observe squeezed states and utilize them in interferometric measurements this inequality in variances must be large (e.g. ≳ 50%). The large phase shifts required to achieve this regime of squeezing can be obtained near the threshold for oscillation of four-wave-mixing in an optical cavity. (2) This paper describes an experimental study(3) of four-wave-mixing in a cavity near threshold using the nonlinear index of the Na atomic resonance.