A laser system comprising two phase-locked solid-state laser sources is described. The laser system can be phase-locked at a predetermined offset between the operating frequencies of the lasers. This is achieved with high precision while exhibiting both low noise and high agility around the predetermined offset frequency. A pulse generator can be employed to generate a series of optical pulses from the laser system, the number, duration and shape of which can all be selected by a user. A phase-lock feedback loop provides a means for predetermined frequency chirps and phase shifts to be introduced throughout a sequence of generated pulses. The laser system can be made highly automated. The above features render the laser system ideally suited for use within coherent control two-state quantum systems, for example atomic interferometry, gyroscopes, precision gravimeters gravity gradiometers and quantum information processing and in particular the generation and control of quantum bits.

A laser apparatus according to an aspect of the present disclosure includes a plurality of semiconductor lasers, a plurality of optical switches disposed in the optical paths of the plurality of respective semiconductor lasers, a wavelength conversion system configured to convert pulsed beams outputted from the plurality of optical switches in terms of wavelength to generate wavelength-converted beams, an ArF excimer laser amplifier configured to amplify the wavelength-converted beams, and a controller configured to control the operations of the plurality of semiconductor lasers and the plurality of optical switches, and the plurality of semiconductor lasers are each configured to output a laser beam so produced that wavelengths of the wavelength-converted beams are wavelengths at which the ArF excimer laser amplifier performs amplification and differ from the optical absorption lines of oxygen.

A purging system for a laser system is described. The purging system comprising a cartridge that houses a desiccant material and which is configured for removable mounting with an enclosure of the laser system. The cartridge comprising a first mesh layer that provides a means for a fluid to flow to the desiccant material housed within the cartridge. The purging system further comprises a membrane located over the first mesh layer. The purging system therefore provides a mean for passively purging the laser system and so its operation does not require the employment of a pump. The employment of the removable cartridge also has the advantage that the downtimes of the laser system with which it is deployed are reduced during periods when it is required to dry or replace the desiccant material.

A femtosecond pulse laser apparatus includes a pump light source configured to provide a pump light, a gain medium configured to obtain a gain of a laser light using the pump light, a first curved mirror and a second curved mirror, which are provided at both sides of the gain medium, an output mirror configured to transmit a portion of the laser light and reflect the other portion of the laser light to the gain medium, a mode locking portion configured to generate a femtosecond pulse of the laser light, and an acoustic wave generator configured to provide an acoustic wave into the gain medium so as to adjust self-phase modulation of the laser light.

An EUV radiation light source generation apparatus includes a pump laser, at least one pulse shaping unit, a wavelength conversion unit, and a high-order harmonics generation unit. The pump laser provides a pulse laser radiation beam. Each pulse shaping unit conducts a spectrum extending operation and a phase compensation operation to the pulse laser radiation beam. The phase compensation operation makes multiple frequency components of the pulse laser radiation beam emitted by the pulse shaping unit to be substantially in phase. The wavelength conversion unit conducts a center wavelength conversion operation to the pulse laser radiation beam. The high-order harmonics generation unit receives the pulse laser radiation beam processed by the pulse shaping unit and the center wavelength conversion operation, and focuses the received pulse laser radiation beam to a high order harmonic generation medium to generate a high order harmonic radiation beam.

An electro-optic modulator (EOM) for altering an optical path length of an optical field is described. The EOM comprises first and second Brewster-angle cut nonlinear crystals having a first and second optical axis. The optical axes are orientated relative to each other such that when an optical field propagates through the nonlinear crystals it experiences no overall deviation. The nonlinear crystals are also arranged to be opposite handed relative to the optical field. The EOM has the advantage that its optical losses are lower when compared with those EOMs known in the art. In addition, the EOM can be inserted into, or removed from, an optical system without any deviation being imparted onto the optical field. This reduces the levels of skill and effort required on the part of an operator. The described method and apparatus for mounting the nonlinear crystals also suppresses problematic piezo-electric resonances within the nonlinear crystals.

An integrated Ti:Sapphire laser device includes a substrate [100], a first waveguide resonator [102] composed of a gain medium integrated onto the substrate in a planar technology configuration, a frequency doubler [104] composed of a second order nonlinear material integrated onto the substrate in a planar technology configuration, and a second waveguide resonator [106] composed of a titanium doped sapphire gain medium integrated onto the substrate in a planar technology configuration.

An M-output, where M>1, chirped pulse amplification chain that includes a stretcher of stretching factor tx_stretch, M amplifiers in cascade, M output compressors respectively placed at the output of each amplifier, wherein it comprises: a partially compressing device placed between the stretcher and the first amplifier, this partially compressing device having at least one partial compression factor, the one (or more than one) partial compression factor(s) being lower than tx_stretch, and an optical switch configured to receive a beam output from the stretcher and to direct it directly to the first amplifier of the cascade or to the partially compressing device depending on the output compressor chosen among the output compressors.

There is described a device for generating electromagnetic field oscillation in a RF device or cavity. The device generally has a photo-diode configured for receiving a laser pulse train and emitting a first electrical signal based thereon, the first electrical signal having a plurality of frequencies; and a harmonics selector configured to output a second electrical signal having one or more frequency of the first electrical signal, the one or more frequency being selected in a manner for the output to generate the electromagnetic field oscillation in the RF device or cavity.

Provided is a method for producing a crystal fiber which can suppress the occurrence of stress birefringence even while distributing a light emission center so as to concentrate on a cross-sectional middle portion. The method for producing a crystal fiber comprises the steps of: using, as a preform, the crystal fiber comprising a light emission center that volatilizes from a melted portion upon the melting of a crystal, and heating a portion or a plurality of portions of the side of the preform, whereby the portion or the plurality of portions of the preform are melted such that only a given amount of the inside of the portion or the plurality of portions of the preform is not melted, to form the melted portion; and sequentially transferring the melted portion in the longitudinal direction of the preform, and cooling the melted portion, whereby the melted portion is continuously recrystallized to form a recrystallized region.