A gain switched dual comb spectroscopy device for spectroscopically detecting a sample substance, comprising a first slave laser light source configured to generate a first frequency comb having a first comb free spectral range, and a second slave laser light source configured to generate a second frequency comb having a second comb free spectral range which is different from the first comb free spectral range. A master laser light source is configured to inject seed light in to both slave laser light sources therewith to injection lock the generation of both the first and the second frequency combs. A photodetector part is arranged to combine the first and the second frequency combs and to detect a beat signal the spectrum of which comprises a third frequency comb including beat tones produced by interference between the combined first and second frequency combs. The device comprises a sample detection area configured for receiving the sample for detection and for directing at least one of the first and the second frequency comb to the photodetector part via the sample detection area.

The present disclosure relates to a device and a method for adjusting a pulse width of a laser beam by using the plasma generated by being induced from laser as a shutter, and more particularly, to a device and a method for adjusting a laser pulse width, which can precisely and quickly adjust the laser pulse width by dividing the laser generated from a laser light source into a target pulse and a shutter pulse; converting the optical path of the divided laser; and chopping the target pulse by using the plasma induced from the shutter pulse as an optical shutter in a cell having adjustable internal pressure.

A method and system for injection-locking multiple optical amplifiers is disclosed. A master laser is employed to generate a continuous-wave output field. Optical modulators then produce first and second seed optical fields from the continuous-wave output field. The first and second seed optical fields provide an input to injection lock one or more optical amplifiers, optionally at different operating frequencies. Since the first and second seed optical fields are generated from the continuous-wave output field then the output fields of the optical amplifiers exhibit a high phase-coherence with each other and with the continuous-wave output field. Employing the first and second optical fields reduces the requirement to induce large frequency shifts on a single optical field. Techniques for phase-locking the output of the injection-locked laser systems are also provided to further reduce phase noise within the systems.

The present invention provides a repetition frequency-tunable optical frequency comb generated by basis of optical feedback. The optical frequency comb comprises a single-frequency laser resonant cavity, a wavelength division multiplexer, a single-mode semiconductor pump light source, an optical circulator, a first optical fiber coupler, a second optical fiber coupler, a photoelectric detector, a highly-stable signal source, an error signal processing system, a laser frequency modulation device and a tunable laser-delay module. The present invention performs delay-time processing to the single-frequency laser by the tunable laser-delay module, and achieves an optical feedback by the optical circulator for injecting to the resonant cavity, generating a series of tunable laser longitudinal modes with equal frequency space. Meanwhile, in combination with the highly-stable signal source, the error signal processing system and the laser frequency modulation device, a laser frequency lock is achieved, and the laser frequency comb is generated. The invention obtains a repetition frequency-tunable laser frequency comb with a simple and practical method, having an extensive application prospect and huge application value in fields such as optical fiber sensing and spectroscopy of atom and molecule.

An optical configuration including axiconical elements that serve as parts of a resonator or an optical chain of an amplifier for an active laser volume with a large transverse dimension. The system may include a single-fold or multiple-folds axiconical elements. One of the system's advantages is providing the means to produce, even with a stable resonator, a high-quality and well-controlled beam, utilizing efficiently a wide active laser medium.

A fiber laser producing a beam of ultrashort laser pulses at a repetition rate greater than 200 MHz includes a linear fiber resonator and a fiber branch. Ultrashort laser pulses are generated by passive mode-locking and circulate within the linear fiber resonator. Each circulating laser pulse is split into a portion that continues propagating in the linear fiber resonator and a complementary portion that propagates through the fiber branch and is then returned to the linear fiber resonator. The optical length of the linear fiber resonator is an integer multiple of the optical length of the fiber branch. The repetition rate of the ultrashort laser pulses is the reciprocal of the propagation time of the laser pulses through the fiber branch.

Apparatus and methods demonstrate a chip-scale direct optical to RF link that frequency divides up to 120 GHz optical frequency combs to 10 GHz using harmonic multi-tone injection locking. The embodied invention links widely separated optical frequency combs in the millimeter wave regime (>120 GHz) or THz domain (100s of GHz to THz domain), e.g., microresonator-based frequency combs, which are currently outside of the photo-detection region, into the microwave domain (10s of GHz) where it can be easily photo-detected and controlled. The technique works as a perfect optical divider, using a mode-locked laser and optical injection locking as the technique to phase-lock both lasers.

Apparatus and methods demonstrate a chip-scale direct optical to RF link that frequency divides up to 120 GHz optical frequency combs to 10 GHz using harmonic multi-tone injection locking. The embodied invention links widely separated optical frequency combs in the millimeter wave regime (>120 GHz) or THz domain (100s of GHz to THz domain), e.g., microresonator-based frequency combs, which are currently outside of the photo-detection region, into the microwave domain (10s of GHz) where it can be easily photo-detected and controlled. The technique works as a perfect optical divider, using a mode-locked laser and optical injection locking as the technique to phase-lock both lasers.

A system for optical comb carrier envelope offset frequency control includes a mode-locked oscillator. The mode-locked oscillator produces an output beam using an input beam and one or more control signals. The output beam includes a controlled carrier envelope offset frequency. A beat note generator produces a beat note signal using a portion of the output beam. A control signal generator produces the one or more control signals to set the beat note signal by modulating the intensity of the input beam within the mode locked oscillator. Modulating the intensity comprises using a Mach-Zehnder intensity modulator or using an intensity modulated external laser to affect a gain medium within the mode-locked laser.

An apparatus may include a diode-pumped solid-state laser oscillator configured to output a pulsed laser beam, a modulator configured to modify an energy and a temporal profile of the pulsed laser beam, and an amplifier configured to amplify an energy of the pulse laser beam. A modified and amplified beam to laser peen a target part may have an energy of about 5 J to about 10 J, an average power (defined as energy (J)frequency (Hz)) of from about 25 W to about 200 W, with a flattop beam uniformity of less than about 0.2. The diode-pumped solid-state oscillator may be configured to output a beam having both a single longitudinal mode and a single transverse mode, and to produce and output beams at a frequency of about 20 Hz.