A surface-emitting semiconductor laser system contains at least one MQW unit of at least three constituent QWs, axially separated from one another substantially non-equidistantly. The MQW unit is located within the axial extent covered, in operation of the laser, by a half-cycle of the standing wave of the field at a wavelength within the gain spectrum of the gain medium; immediately neighboring nodes of the standing wave are on opposite sides of the MQW unit. So-configured MQW unit can be repeated multiple times and/or complemented with individual QWs disposed outside of the half-cycle of the standing wave with which such MQW unit is associated. The semiconductor laser further includes a pump source configured to input energy in the semiconductor gain medium and a mode-locking element to initiate mode-locking.

Methods, systems, and devices are disclosed for divided-pulse lasers. In one aspect, a pulsed laser is provided to include a laser cavity including an optical amplifier and a plurality of optical dividing elements and configured to direct a laser pulse of linearly polarized light into the plurality of optical dividing elements to divide the light of the laser pulse into a sequence of divided pulses each having a pulse energy being a portion of the energy of the laser pulse before entry of the optical dividing elements, to subsequently direct the divided pulses into the optical amplifier to produce amplified divided pulses. The laser cavity is configured to direct the amplified divided pulses back into the plurality of optical dividing elements for a second time in an opposite direction to recombine the amplified divided pulses into a single laser pulse with greater pulse energy as an output pulse of the laser cavity.

To provide a laser processing machine, a processing method, and a laser light source that are capable of miniaturization. The laser processing machine includes a laser light source and an optical system. The laser light source includes a light emitting body including a substrate and a bottom emission type vertical-cavity surface-emitting laser element that is provided on one surface of the substrate and emits an excitation light beam from another surface side of the substrate, and a cavity that is disposed in contact with the light emitting body on the other surface side of the substrate and oscillates a pulsed laser beam by incidence of the excitation light beam. The optical system causes the pulsed laser beam to contract and applies the pulsed laser beam to a workpiece.

To provide a laser processing machine, a processing method, and a laser light source that are capable of miniaturization. The laser processing machine includes a laser light source and an optical system. The laser light source includes a light emitting body including a substrate and a bottom emission type vertical-cavity surface-emitting laser element that is provided on one surface of the substrate and emits an excitation light beam from another surface side of the substrate, and a cavity that is disposed in contact with the light emitting body on the other surface side of the substrate and oscillates a pulsed laser beam by incidence of the excitation light beam. The optical system causes the pulsed laser beam to contract and applies the pulsed laser beam to a workpiece.

A photonic-based microwave generator includes a mode-locked laser that generates an optical pulse train, a feedback photodiode that samples the optical pulse train, and a servo amplifier that processes the photodiode output into a servo signal. The servo signal controls the mode-locked laser to suppress relative intensity noise on the optical pulse train. The microwave generator may also include a microwave photodiode for converting the optical pulse train into a microwave signal. The microwave generator may also include a second servo amplifier that processes a low-frequency output of the microwave photodiode into a second servo signal that drives an optical modulator that modulates the optical pulse train. The microwave photodiode, optical modulator, and servo amplifier form a feedback loop that suppresses amplitude noise on the microwave signal. By reducing amplitude noise and relative intensity noise, phase noise caused by amplitude-to-phase noise conversion is minimized.

A photonic-based microwave generator includes a mode-locked laser that generates an optical pulse train, a feedback photodiode that samples the optical pulse train, and a servo amplifier that processes the photodiode output into a servo signal. The servo signal controls the mode-locked laser to suppress relative intensity noise on the optical pulse train. The microwave generator may also include a microwave photodiode for converting the optical pulse train into a microwave signal. The microwave generator may also include a second servo amplifier that processes a low-frequency output of the microwave photodiode into a second servo signal that drives an optical modulator that modulates the optical pulse train. The microwave photodiode, optical modulator, and servo amplifier form a feedback loop that suppresses amplitude noise on the microwave signal. By reducing amplitude noise and relative intensity noise, phase noise caused by amplitude-to-phase noise conversion is minimized.

A quasi-monolithic solid-state laser in which the optical components of the laser cavity are bonded to a common substrate via mounts. The optical components and their mounts are fixedly connected to each other and to the substrate by bonding. While the gain medium is bonded to a mount made of a different material with high thermal conductivity for heat sinking, the cavity's lens and mirror components and their mounts are all made of the same material as the substrate, or a different material that is thermally matched to the substrate, and fixedly mounted on the substrate solely with bonding. The bonding is achieved with adhesive bonding, or some other form of bonding such as molecular bonding, chemically activated direct bonding or hydroxide catalysis bonding.

An apparatus for emitting electromagnetic radiation includes a gain element, an optical arrangement defining a resonator and arranged to re-direct radiation emitted by the gain element along a beam path back onto the gain element, the optical arrangement including an output coupler configured to couple a portion of the radiation in the resonator out of the resonator, and a pump arrangement configured to pump the gain element. The optical arrangement further includes a passive device placed in the resonator in the beam path, the passive device having at least two surface portions at an angle to each other. The passive device is arranged to direct first radiation portions and second radiation portions of the radiation, which first and second radiation portions are incident on different ones of the surface portions, to be spatially separated. The apparatus is suitable as a source of dual-comb pulsed laser radiation.

An apparatus for emitting electromagnetic radiation includes a gain element, an optical arrangement defining a resonator and arranged to re-direct radiation emitted by the gain element along a beam path back onto the gain element, the optical arrangement including an output coupler configured to couple a portion of the radiation in the resonator out of the resonator, and a pump arrangement configured to pump the gain element. The optical arrangement further includes a passive device placed in the resonator in the beam path, the passive device having at least two surface portions at an angle to each other. The passive device is arranged to direct first radiation portions and second radiation portions of the radiation, which first and second radiation portions are incident on different ones of the surface portions, to be spatially separated. The apparatus is suitable as a source of dual-comb pulsed laser radiation.

Various example embodiments relate to the field of fiber laser technology. A fiber laser may comprise an active optical fiber configured to amplify an optical signal and a frequency shifter, which may be optically coupled to the active optical fiber. The frequency shifter may be configured to cause a frequency shift to the optical signal in a first direction. The fiber laser may further comprise a bandpass filter, which may be optically coupled to the frequency shifter. The bandpass filter and the active optical fiber may be configured to induce a reverse frequency shift to the optical signal in a second direction opposite to the first direction.