Fabry-Perot Laser Amplifier Research Articles

Low-Noise Parametric Resonant Amplifier

We propose a resonant parametric amplifier with an enhanced noise performance by exploiting the noise-squeezing effect. Noise squeezing occurs through the phase-sensitive amplification process and suppresses one of the two quadrature components of the input noise. When the input signal is only in the direction of the nonsuppressed quadrature component, squeezing can lower that noise figure by almost 3 dB. The resonant structure of the proposed amplifier is inspired by a Fabry-Perot laser amplifier to achieve the squeezing effect using a low number of LC elements. We design and simulate the proposed noise-squeezing parametric amplifier in a conventional 65-nm CMOS process. A minimum noise-squeezing factor of -0.35 dB is achieved with a signal gain of 26 dB for one quadrature component of a 10-GHz narrow-band signal.

Long-Cavity Fabry–Perot Laser Amplifier Transmitter With Enhanced Injection-Locking Bandwidth for WDM-PON Application

We simulate the injection-locking performance of a 1% antireflection coated Fabry-Perot laser amplifier (AR-FPLA) and demonstrate the 2.5-Gbit/s DWDM-PON application with the directly modulated AR-FPLA based ONU transmitter under side-mode injection-locking condition. The effect of the AR-FPLA front-facet reflectivity on the injection locking range detuning and the Q-factor are interpreted from theoretical simulations and are experimentally characterized. A 25-channel locking capacity is reported for such a side-mode injection-locked AR-FPLA with corresponding wavelength locking range of 30 nm, the minimal requested power of -7 dBm and gain extinction ratio of <;7 dB by reducing its front-facet reflectivity to 1%. At bit rate of 2.5 Gbit/s, the BER of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-12</sup> is achievable for the nearest 17 channels of AR-FPLA at receiving power of -21 dBm, and all of the 25 injection-locked channels with SMSR of > 35 dB can guarantee the BER of <; 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-9</sup> with their worst receiving sensitivity degrading to -19 dBm.

Measurements and modeling of reflective bistability in 1.55-μm laser diode amplifiers

We present experimental measurements of bistable characteristics for the case of a 1.55-/spl mu/m symmetric Fabry-Perot laser amplifier with a particularly rich variety of behavior for reflected signals. Three main forms of hysteresis loops are observed on reflection. The hysteresis loop changes from anticlockwise to clockwise hysteresis in the optical output-input characteristic when the drive current or initial phase detuning is changed. A butterfly hysteresis loop is observed experimentally at an optical input power as low as 300 /spl mu/W for a drive current equal to 94% of the lasing threshold. The dependence of the reflective optical bistability on drive current, initial phase detuning, and injected optical pewter has been investigated for the first time in an uncoated 1.55-/spl mu/m amplifier. Measurements of the device voltage shifts on switching reveal hysteresis loops which match those in the corresponding optical powers and which indicate the amount of gain saturation and nonlinear refraction responsible for bistability. An analytical model is used to describe the observed reflective bistability and to give insight into the detailed physical mechanisms responsible.

Responsivity measurement of Fabry-Perot laser amplifier detectors

It is shown that a Fabry-Perot laser diode detector exhibits a local responsivity peak when biased at a level between transparency and threshold. In this regime the detector functions as a resonant amplifier and produces a junction voltage that depends on the input optical power. The switching time to this state, from a bias point above threshold, is below 5 ns. Experimentally observed peak responsivities compare favorably with theoretical values.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

High-speed photodetection characteristics of a Fabry-Perot laser amplifier under AM and FM formats

A comparison between the photodetection characteristics of an FP laser amplifier under AM and FM formats is reported. A 450 MHz photodetection bandwidth is obtained under the AM format using a Fabry-Perot laser amplifier, with two antireflection coated facets with 10 -5 reflectivity. Using an FP laser amplifier with 10 -3 reflectivity as an FM discriminator/photodetector, a photodetection bandwidth of up to 2.6 GHz was measured

Simple Approximate Theory for Twin-guide Fabry-Perot Laser Amplifier Switches

Abstract A simple modal analysis is presented of twin-stripe semiconductor Fabry-Perot laser amplifier switches that operate via simultaneous changes in gain and refractive index due to free carrier injection. The analysis of Adams [3], based on weak coupled mode theory, is first briefly reviewed, and compared with the modal method. An approximate solution is then derived, which shows good agreement with the full theory. Approximate resonance and lasing conditions are also found, and limiting values for switch crosstalk are estimated.

Optical switching in the twin-guide Fabry-Perot laser amplifier

A recently developed theory of the twin-guide Fabry-Perot laser amplifier has been extended to include the case of optically induced switching. The effect of feedback from the facets serves to dramatically decrease the optical power required for switching as compared to that for a traveling-wave amplifier, but at the expense of accurate control of input wavelength. Switching is predicted at input powers on the order of microwatts, in good agreement with a first experimental demonstration of the effect.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Optical bistability in semiconductor injection lasers

This paper reviews optical bistability in semiconductor lasers, with particular reference to the potential switching speeds of the systems demonstrated to date. Devices which switch by redistributing a nearly constant number of carriers within the active region should be faster, although less stable, than systems whose transitions are attended by large changes in carrier numbers. One system of the former type, the self-focused coupled cavity laser, is analysed in some detail and is compared with the twin-stripe laser and the Fabry-Perot laser amplifier.

Assessment of switching speed of optical bistability in semiconductor laser amplifiers

Measured hysteresis characteristics are presented for a bistable Fabry-Perot laser amplifier operating at high switching rates. The results show that optical bistability ceases to be evident at a repetition frequency of around 250 MHz, corresponding to a data rate of 500 Mbit/s, which indicates switching times commensurate with the carrier recombination time.