A fiber laser system based in solitonic passive mode-locking, including a laser diode to emit and deliver an optical signal of a first wavelength; a single-fiber laser cavity including a dichroic mirror, a SESAM and a polarization maintaining highly-doped active fiber, to receive the emitted signal and to emit a pulsed optical signal of a second wavelength, generating laser light in the form of mode-locked ultrashort pulses; a unit coupling the laser diode to the single-fiber laser cavity; and an isolator device protecting the cavity from back reflections. The solitonic mode-locked ultrashort pulses are comprised in a range of 100 fs<10 ps with repetition rates of hundreds MHz to tens of GHz.

A method of performing coherent anti-stokes Raman spectroscopy (CARS) includes generating first and second optical pulse trains having different and adjustable repetition rates. One of the pulse trains is directed in a CW direction and the other in a CCW direction. A frequency shift and a first linear chirp is applied to optical pulses in the first optical pulse train. A second linear chirp is applied to optical pulses in the second optical pulse train. The first and second linear chirps having a common chirp rate. One of the chirped optical pulse trains is used as a pump beam and the other is used as a Stokes beam. The first and second chirped optical pulse trains are combined to define a combined beam. The combined beam is provided to a CARS spectroscopic system for exciting a resonant mode in a sample and generating a CARS signal.

The invention relates to a device (1) for generating laser pulses, comprising a pump laser (1), which emits laser pulses at a pump wavelength (12) with a repetition frequency, wherein the pulse duration of the laser pulses is 0.5-100 ps, and an optical parametric oscillator (3) that converts the laser pulses of the pump laser (1) at least partially to laser pulses at a signal wavelength (10) and at an idler wavelength (11), which differs from the former, wherein the optical parametric oscillator (3) has an optical resonator (20), comprising a non-linear wavelength converter (22), which converts the laser pulses of the pump laser (1) to laser pulses at the signal wavelength (10) and at the idler wavelength (11), and an output coupling element (24), which couples at least some of the radiation out of the optical resonator (20). It is an object of the invention to provide a device that makes efficient generation of synchronous laser pulse trains with two different central wavelengths possible, wherein the available tuning range with respect to the gap of the central wavelengths is intended to be enlarged with respect to the prior art. To this end, the invention proposes that the pump laser (1) is tunable with respect to the pump wavelength (12) and the repetition frequency, wherein the resonator (20) has an optical fiber (23) with a dispersion in the range of 10-100 ps/nm and a length of 10-1000 m. The invention furthermore relates to a method for generating laser pulses using such a device.

A method and apparatus for characterizing an optical element. The optical element is part of a laser and is mounted on a translation stage to scan the optical element transverse to an intracavity laser beam. A performance characteristic of the laser is recorded as a function of position of the optical element.

A laser system, comprised of: a laser cavity; a gain medium a pump, a saturable absorber (SA); a first mirror and a second mirror; wherein a ratio of an area of the beam area within the SA to an area of the laser beam within the gain medium is greater than 1, and wherein the beam generates a gain medium radius spot on the gain medium and a saturable absorber radius spot on the saturable absorber such that a ratio between a saturable absorber radius spot on the saturable absorber and the gain medium radius spot on the gain medium is within a range of 1.7-7 is disclosed. A method for using the laser system e.g., for producing a pulsed energy is further disclosed.

Free-space optical (FSO) wireless transmission, including optical communications, remote-sensing, power beaming, etc., can be enhanced by replacing conventional laser sources that operate in the infrared portion of the optical spectrum with ultra-short pulsed laser (USPL) sources having peak pulse powers of one kWatt or greater and pulse lengths of less than one picosecond. Specifically, it has been observed that under these conditions the attenuation of an USPL beam having the same average optical power as a conventional laser in a lossy medium, such as the atmosphere, is substantially less than the attenuation of a conventional laser beam having a lower peak pulse power and/or a longer pulse width. The superior system performance when using an USPL can be translated into an increased distance between a laser source in a transmitter and a photodetector in receiver and/or a higher reliability of system operation in inclement weather conditions.

A method for generating a single-cavity dualcomb or multicomb for laser spectroscopy, the method comprising the steps of providing a laser system comprising a pump source, a gain medium, and a resonator having a spectral filter; spectrally filtering, by the spectral filter, light in the resonator and attenuating, in particular blocking, by the spectral filter, one or more wavelength bands at least one of which being located completely within the gain bandwidth of the laser system such that two or more at least partially separated spectral regions are provided; mode-locking the two or more at least partially separated spectral regions.

Systems and methods are described for producing an amplitude-modulated laser pulse train. The laser pulse train can be used to cause fluorescence in materials at which the pulse trains are directed. The parameters of the laser pulse train are selected to increase fluorescence relative to a constant-amplitude laser pulse train. The amplitude-modulated laser pulse trains produced using the teachings of this invention can be used to enable detection of specific molecules in applications such as gene or protein sequencing.

An optical assembly provides dispersion control, modelocking, spectral filtering, and/or the like in a laser cavity. For example, the optical assembly may comprise a diffraction grating pair arranged to temporally and spatially disperse a beam on a forward pass through the optical assembly, a reflective device at an end of the optical assembly, and a focusing optic arranged to create a beam waist at the reflective device. The beam waist created at the reflective device may cause the beam to be inverted on a reverse pass through the optical assembly, and a temporal dispersion and a spatial dispersion of the beam may be doubled on the reverse pass through the optical assembly to form a temporally and spatially dispersed output from the optical assembly.

A pulse stretching fiber oscillator (or laser cavity) may comprise a chirped fiber Bragg grating (CFBG) and an optical circulator arranged such that a first portion of a beam that is transmitted through the CFBG continues to propagate through the laser cavity while a second portion of the beam that is reflected from the CFBG is stretched and chirped by the CFBG and directed out of the laser cavity by the optical circulator. Accordingly, a configuration of the CFBG and the optical circulator in the laser cavity may enable pulse stretching contemporaneous with outcoupling, which may prevent deleterious nonlinear phase from accumulating prior to stretching.