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

Annual Meeting Optical Society of America

Superregenerative detection: experiment and theory

Ian C. M. Littler, Stefan Balle, Klaas Bergmann, Gautam Vemuri, Rajarshi Roy

Published Jan 1, 1989• 0 citations
Publisher

Abstract

The initiation time for the intensity of an injection seeded laser is measured as a function of the externally injected signal strength. The operation of a radiation detector based on the measurement of initiation times is demonstrated, with a dynamic range of 7 orders of magnitude, bandwidth resolution of 5 MHz, and tuning range limited by the active medium of the laser employed. Such a detector, based on the Q-switched operation of an oscillator, is known as a superregenerative receiver. We report experimental measurements of the characteristics of such a receiver and explain the behavior with reference to a simple stochastic model of a laser with an injected signal. The weakest signals that can be detected are shown to be comparable to the level of spontaneous emission into the cavity mode, which corresponds to an average photon number less than unity for our system.

DOI
10.1364/oam.1989.fv2

Related papers

Detection of weak signals via the decay of an unstable state: Initiation of an injection-seeded laser

Ian C. M. Littler, Stefan Balle, Klaas Bergmann +2 more

We have demonstrated the detection of weak optical signals via the decay of an unstable state. A Q-switched laser is an example of an unstable state, the decay of which has to be triggered either by quantum fluctuations or by an injected external signal. Measurement of the initiation time of the laser intensity allows us to determine the strength of the external signal with a dynamic range of 7 orders of magnitude. It is possible to detect signal levels that correspond to less than one photon in a selected cavity mode.

Physical Review A•Apr 1, 1990•29 citations

Super-regenerative laser receiver: Transient dynamics of a laser with an external signal

Gautam Vemuri, Rajarshi Roy

In super-regenerative detection, a weak external signal is amplified in an oscillator that is periodically switched on and then quenched. It is shown that very weak optical signals, slightly above the noise level, can be detected effectively by a laser used as a super-regenerative receiver. The detector output for different signal levels and its operating characteristics are determined by numerical integration of stochastic differential equations that represent the growth of laser radiation from a background consisting of signal and noise.

Physical Review A•Mar 1, 1989•43 citations

Detection of a weak external signal via the switch-on-time statistics of a semiconductor laser

M. C. Torrent, S. Balle, Maxi San Miguel +1 more

We calculate the passage-time statistics of a gain-switched single-mode semiconductor laser with a weak, detuned injected signal. Results are given in terms of a relevant scaling parameter. We find that a weak injected signal can be detected by measurements of the mean passage time or its variance whenever its frequency is close to the one of the semiconductor lasers in the on state. In this case, the external signal is resonant with the laser field at the time when amplification becomes possible, and hence it triggers the switch-on more efficiently. The detection bandwidth is of the order of 50 GHz for the case considered.

Physical Review A•Apr 1, 1993•10 citations

Passage-time calculation for the detection of weak signals via the transient dynamics of a laser

S. Balle, FERDINANDO DE PASQUALE, Maxi San Miguel

The passage-time (PT) distribution associated with the switch on of a laser with an injected signal can be used to detect weak signals. We calculate the distribution function of such a distribution. Results for the mean PT interpolate between the limit of no injected signal and a simple logarithmic law for strong signals. It has a scaling form with a single important independent parameter. The variance of the distribution is more sensitive to the presence of the injected signal than the mean. Explicit formulas for the limit of sensitivity of the detection method and for the bandwidth resolution are given.

Physical Review A•May 1, 1990•32 citations

Heterodyne detection with an injection laser I. principle of operation and conversion efficiency

Dietrich Marcuse

If a light signal is passed into the resonant cavity of an actively oscillating injection laser, an electrical signal at the difference between the laser and light signal frequencies flows through the wire supplying the DC bias to the laser. A small-signal analysis of heterodyne detection with such a laser oscillator that is based solely on rate equations and introduces the externally applied signal as a source term into the photon rate equation is discussed. Since neither Maxwell's equations nor the wave equation are involved, this analysis is deemed simpler and more transparent than that reported earlier. Gain saturation of the active medium of the laser, which is responsible for broadening of the relaxation resonance, is taken into account.

IEEE Journal of Quantum Electronics•Jan 1, 1990•9 citations

Coherent laser detection by frequency-shifted optical feedback

Éric Lacot, R. Day, F. Stoeckel

The dynamical response of a laser to frequency-shifted optical feedback is investigated both theoretically and experimentally. The ultrahigh sensitivity of a class-B laser (i.e., a laser with a cavity damping rate ${\ensuremath{\gamma}}_{c}$ higher than the population damping rate ${\ensuremath{\gamma}}_{1})$ to external light injection is demonstrated by the optical detection of weak optical feedback. Compared to a conventional optical beating, the intensity modulation induced by the coherent interaction between the laser electric field and the frequency-shifted reinjected electric field can be several orders of magnitude higher. This method permits high sensitive interferometry and hence imaging. We call this laser detection technique laser optical feedback imaging (LOFI). When the optical frequency shift is resonant with the laser relaxation frequency, the intracavity amplification of the beating is maximum and the enhancement is given by the laser damping rate ratio ${\ensuremath{\gamma}}_{c}/{\ensuremath{\gamma}}_{1}.$ This amplification is of the order of ${10}^{6}$ for a microchip laser. We also show that without optical feedback the strong fluctuations of the laser output power are well described by the Langevin noise process. In a broad range around the laser relaxation frequency the laser quantum noise is also resonantly amplified and is then several orders of magnitude higher than the detector noise. In these conditions, the LOFI is a shot noise limited detection technique. Reflectivity as low as ${10}^{\ensuremath{-}13}$ is then easily detectable with a laser output power of a few milliwatts with a detection bandwidth of 1 kHz. Experimentally, for weak optical feedback the laser fluctuations are principally composed of the LOFI modulation signal at the shifted frequency and of the laser quantum noise amplified at the relaxation frequency. For strong optical feedback, nonlinear effects appear in the laser dynamics. In these conditions, harmonics and parametrics peaks appear in the power spectrum. The LOFI detection system is then saturated.

Physical Review A•Sep 19, 2001•134 citations
The initiation time for the intensity of an injection seeded laser is measured as a function of the externally injected signal strength. The operation of a radiation detector based on the measurement of initiation times is demonstrated, with a dynamic range of 7 orders of magnitude, bandwidth resolution of 5 MHz, and tuning range limited by the active medium of the laser employed. Such a detector, based on the Q-switched operation of an oscillator, is known as a superregenerative receiver. We report experimental measurements of the characteristics of such a receiver and explain the behavior with reference to a simple stochastic model of a laser with an injected signal. The weakest signals that can be detected are shown to be comparable to the level of spontaneous emission into the cavity mode, which corresponds to an average photon number less than unity for our system.
We have demonstrated the detection of weak optical signals via the decay of an unstable state. A Q-switched laser is an example of an unstable state, the decay of which has to be triggered either by quantum fluctuations or by an injected external signal. Measurement of the initiation time of the laser intensity allows us to determine the strength of the external signal with a dynamic range of 7 orders of magnitude. It is possible to detect signal levels that correspond to less than one photon in a selected cavity mode.
In super-regenerative detection, a weak external signal is amplified in an oscillator that is periodically switched on and then quenched. It is shown that very weak optical signals, slightly above the noise level, can be detected effectively by a laser used as a super-regenerative receiver. The detector output for different signal levels and its operating characteristics are determined by numerical integration of stochastic differential equations that represent the growth of laser radiation from a background consisting of signal and noise.
We calculate the passage-time statistics of a gain-switched single-mode semiconductor laser with a weak, detuned injected signal. Results are given in terms of a relevant scaling parameter. We find that a weak injected signal can be detected by measurements of the mean passage time or its variance whenever its frequency is close to the one of the semiconductor lasers in the on state. In this case, the external signal is resonant with the laser field at the time when amplification becomes possible, and hence it triggers the switch-on more efficiently. The detection bandwidth is of the order of 50 GHz for the case considered.
The passage-time (PT) distribution associated with the switch on of a laser with an injected signal can be used to detect weak signals. We calculate the distribution function of such a distribution. Results for the mean PT interpolate between the limit of no injected signal and a simple logarithmic law for strong signals. It has a scaling form with a single important independent parameter. The variance of the distribution is more sensitive to the presence of the injected signal than the mean. Explicit formulas for the limit of sensitivity of the detection method and for the bandwidth resolution are given.
If a light signal is passed into the resonant cavity of an actively oscillating injection laser, an electrical signal at the difference between the laser and light signal frequencies flows through the wire supplying the DC bias to the laser. A small-signal analysis of heterodyne detection with such a laser oscillator that is based solely on rate equations and introduces the externally applied signal as a source term into the photon rate equation is discussed. Since neither Maxwell's equations nor the wave equation are involved, this analysis is deemed simpler and more transparent than that reported earlier. Gain saturation of the active medium of the laser, which is responsible for broadening of the relaxation resonance, is taken into account.
The dynamical response of a laser to frequency-shifted optical feedback is investigated both theoretically and experimentally. The ultrahigh sensitivity of a class-B laser (i.e., a laser with a cavity damping rate ${\ensuremath{\gamma}}_{c}$ higher than the population damping rate ${\ensuremath{\gamma}}_{1})$ to external light injection is demonstrated by the optical detection of weak optical feedback. Compared to a conventional optical beating, the intensity modulation induced by the coherent interaction between the laser electric field and the frequency-shifted reinjected electric field can be several orders of magnitude higher. This method permits high sensitive interferometry and hence imaging. We call this laser detection technique laser optical feedback imaging (LOFI). When the optical frequency shift is resonant with the laser relaxation frequency, the intracavity amplification of the beating is maximum and the enhancement is given by the laser damping rate ratio ${\ensuremath{\gamma}}_{c}/{\ensuremath{\gamma}}_{1}.$ This amplification is of the order of 106{10}^{6}106 for a microchip laser. We also show that without optical feedback the strong fluctuations of the laser output power are well described by the Langevin noise process. In a broad range around the laser relaxation frequency the laser quantum noise is also resonantly amplified and is then several orders of magnitude higher than the detector noise. In these conditions, the LOFI is a shot noise limited detection technique. Reflectivity as low as ${10}^{\ensuremath{-}13}$ is then easily detectable with a laser output power of a few milliwatts with a detection bandwidth of 1 kHz. Experimentally, for weak optical feedback the laser fluctuations are principally composed of the LOFI modulation signal at the shifted frequency and of the laser quantum noise amplified at the relaxation frequency. For strong optical feedback, nonlinear effects appear in the laser dynamics. In these conditions, harmonics and parametrics peaks appear in the power spectrum. The LOFI detection system is then saturated.