Noise transfer functions of mode-locked semiconductor laser

The noise behavior of mode-locked semiconductor ring laser, including timing jitter, and pulse energy fluctuation are investigated using the notion of a noise transfer function. Numerical simulation predicts that semiconductor mode-locked lasers have very complex structure in the transfer function which is confirmed experimentally by corresponding noise measurements

High Speed Pulse Slicer/Demultiplexer With Gain For Use In Solid State Regenerative Amplifier Systems

A mode-locked solid state laser is disclosed for generating ultrashort optical pulses from a semiconductor type laser. A semiconductor pulse slicer/demultiplexer/modulator with gain amplification is used to modulate and amplify a generated optical beam whether or not the beam is pulsed, continuous wave, q-switched, or modelocked. Alternatively, the semiconductor pulse slicer/demultiplexer/modulator with gain amplification is used to gate a generated optical beam whether or not the beam is pulsed, continuous wave, q-switched, or modelocked. Alternatively, the semiconductor pulse slicer/demultiplexer/modulator with gain amplification is used to demultiplex a generated optical beam whether or not the beam is pulsed, continuous wave, q-switched, or modelocked. The invention uses only semiconductor type materials such as Titanium Saphire, Gallium Arsenide, Aluminum Gallium Arsenide (GaAs/AlGaAs) as both the pulse slicer/demultiplexer/modulator with gain amplification, and the mode-locked l

Ultralow Noise Mode-locked Laser and RF Sinewave Source. DIV

Systems, devices and methods of generating both a precision electrical timing signal as well as a precision optical timing signal. A novel, modified opto-electronic loop oscillator is used to drive a harmonic mode-locked laser. A novel opto-electronic loop has a larger Q factor by increasing the electrical loop oscillating frequency w0 by using a beat note created by the selection of two optical longitudinal modes from the modelocked laser. The beat note is detected and divided down to drive a modulator that modelocks the laser. The frequency division stage also reduces the noise

High Precision Measurement of the Free Spectral Range of an Etalon

Methods, systems, apparatus and devices for using a modified PDH technique to measure the FSR of an etalon with one part per l0^4 precision. This method is especially useful for etalons with small FSR (less than 10 GHz) because this method does not require a high resolution OSA or tuneable laser. As the ITU grid for DWDM becomes denser, this method will have a larger impact on the FSR measurement of etalons

Optical Frequency Self Sabilization in a Couple of Optoelectronic Oscillator

Methods and devices for a coupled optoelectronic oscillator having optical frequency stabilization. The coupled optoelectronic oscillator includes a harmonically mode-locked laser cavity having a Mach-Zehnder modulator for mode-locking and an intracavity Fabry-Perot etalon to allow only one single supermode to lase, a stabilization loop coupled with the Fabry-Perot etalon to detect changes in the laser cavity optical frequency and generate an error signal to compensate for the frequency change to stabilize the mode-locking of the laser frequency stabilization, and an electrical loop between the laser cavity and the stabilization loop for driving the Mach-Zehnder modulator with the coupled optoelectronic oscillator signal

Two-mode beat phase noise of actively modelocked lasers

An analytic expression for the phase noise spectrum is estimated when two arbitrary longitudinal modes are selected for beating from the output of an actively modelocked laser. A separate experiment confirmed the theory qualitatively. It was found that two- mode beating posseses more phase noise than the beating involving the entire mode spectrum, especially at low offset frequency, even though two mode beating noise is decoupled from the RF oscillator noise to the first order

Demonstration Of Extended Rf Chirp Generation Via Time Division Multiplexing

We have demonstrated a novel modulation scheme based on TDM to extend the frequency span of a chirped RF signal. Extended RF chirp we have generated agrees very well with the conventional RF chirp signal. © 2005 IEEE

Demonstration Of Endless Phase Modulation For Arbitrary Waveform Generation

We have developed a novel modulation scheme for shifting the frequency of an optical beat signal by improving a conventional serrodyne system via time division multiplexing. This novel method acts as an endless phase modulator where the phase linearly increases from zero phase to infinite phase. With this method, we have shifted a 25-GHz carrier continuously up to 1-MHz offset with 43-dB spur-free dynamic range, which is 7 dB higher than an ordinary serrodyne method. © 2005 IEEE

Intracavity Gain Dynamics And Their Role In Mode-Locked Semiconductor Diode Lasers

In this paper, we present the intracavity gain dynamics of hybrid modelocked external cavity semiconductor lasers. Using the pump-probe method, the optical gain and transmittance of a modelocked external cavity laser diode and saturable absorber were measured, respectively. The pulse shaping processes were measured by investigating the chirp of the optical pulse at the output coupler, before and after the saturable absorber. These measurements were obtained by a spectrally resolved cross correlation technique. In comparison with the previous studies of the single pass dynamics in semiconductor optical amplifiers, the dynamics of the nonlinearities affecting the pulse shaping within the laser cavity is less dramatic owing to the longer intracavity pulse widths. It was also observed that the linear GVD plays an important role in the shaping of the pulse envelop and linearizing the pulse chirp