A surface-emitting laser includes an active layer; multiple reflectors sandwiching the active layer; and an electrode pair connected to a power supply, through which a current is injected into the active layer. The surface-emitting laser emits at least one laser beam during a current injection period when the current injected into the active layer through the electrode pair during the current injection period is a first current and emits at least one laser beam during a current decrease period when the current injected into the active layer through the electrode pair during the current injection period is a second current exceeding the first current. The current decrease period is after the current injection period. The current injected into the active layer during the current decrease period is lower than the current injected into the active layer during the current injection period.

An extremely sensitive spectroscopy method utilizes a laser modified to an extremely low emission with an integrated control system, interfaced within a typical Raman platform to comprise low energy laser spectroscopy (LELS). LELS acquires and utilizes a quantum entangled state of photons and particles, including omnipresent cosmological dark matter particles (OCDM) and omnipresent cosmological dark energy (OCDE). The OCDM and OCDE matter has an affinity to particles of same OCDM and OCDE matter in target specimens, with same-time data results of high sensitivity. In a semiconductor light emitter, electron flow at a low energy level is provided to a quantum well to produce a quantum tunneling of electrons into an active region of the laser quantum well and creating sublasering. Sublasering allows OCDM and OCDE to become entangled with other particles and energies in the laser's quantum well and create a transmission package comprising quantum entangled fields, waves, wave packages, states and energies. Providing a triggering pulse causes a second tunneling, carrying the transmission package for emission.

An extremely sensitive spectroscopy method utilizes a laser modified to an extremely low emission with an integrated control system, interfaced within a typical Raman platform to comprise low energy laser spectroscopy (LELS). LELS acquires and utilizes a quantum entangled state of photons and particles, including omnipresent cosmological dark matter particles (OCDM) and omnipresent cosmological dark energy (OCDE). The OCDM and OCDE matter has an affinity to particles of same OCDM and OCDE matter in target specimens, with same-time data results of high sensitivity. In a semiconductor light emitter, electron flow at a low energy level is provided to a quantum well to produce a quantum tunneling of electrons into an active region of the laser quantum well and creating sublasering. Sublasering allows OCDM and OCDE to become entangled with other particles and energies in the laser's quantum well and create a transmission package comprising quantum entangled fields, waves, wave packages, states and energies. Providing a triggering pulse causes a second tunneling, carrying the transmission package for emission.

In a semiconductor laser according to an embodiment of the present disclosure, a ridge part has a structure in which a plurality of gain regions and a plurality of Q-switch regions are each disposed alternately with each of separation regions being interposed therebetween in an extending direction of the ridge part. The separation regions each have a separation groove that separates from each other, by a space, the gain region and the Q-switch region adjacent to each other. The separation groove has a bottom surface at a position, in a second semiconductor layer, higher than a part corresponding to a foot of each of both sides of the ridge part. The semiconductor laser includes an electrode provided over the bottom surface of each separation groove with an insulating layer being interposed therebetween.

In a semiconductor laser according to an embodiment of the present disclosure, a ridge part has a structure in which a plurality of gain regions and a plurality of Q-switch regions are each disposed alternately with each of separation regions being interposed therebetween in an extending direction of the ridge part. The separation regions each have a separation groove that separates from each other, by a space, the gain region and the Q-switch region adjacent to each other. The separation groove has a bottom surface at a position, in a second semiconductor layer, higher than a part corresponding to a foot of each of both sides of the ridge part.

For example, an influence of a tail in a laser pulse is reduced. A semiconductor laser includes at least two or more gain regions and at least two or more absorption regions formed on a semiconductor substrate, in which the gain regions and the absorption regions include a continuous active layer, and the gain regions and the absorption regions are alternately formed via a separation region, and from a front end surface, a first laser pulse having a first polarized light is emitted and a second laser pulse having a second polarized light is subsequently emitted, and the first polarized light and the second polarized light are orthogonal to each other.

Systems and methods for imaging in the short wave infrared (SWIR), photodetectors with low dark current and associated circuits for reducing dark currents and methods for generating image information based on data of a photodetector array. A SWIR imaging system may include a pulsed illumination source operative to emit radiation pulses in the SWIR band towards a target resulting in reflected radiation from the target; (b) an imaging receiver including a plurality of Ge PDs operative to detect the reflected SWIR radiation and a controller, operative to control activation of the receiver for an integration time during which the accumulated dark current noise does not exceed the time independent readout noise.

This invention discloses an improved laser induced breakdown spectroscopy (LIBS) apparatus and method for the detection of mineral and metal contamination in liquid samples. The mineral and metal contaminant is first collected by filtering the liquid sample with a membrane filter. The membrane filter with the mineral and metal contaminant is then measured by a LIBS apparatus. The LIBS apparatus is based on a high repetition rate pulsed laser. The laser produces a train of laser pulses at a high repetition rate in the kHz (or even higher) range. When the laser beam hits the surface of the membrane filter, it generates several thousands of micro-plasma emissions per second. Synchronized miniature CCD array optical spectrometer modules collect the LIBS signal from these micro-plasma emissions. By adjusting the integration time of the spectrometer to cover a plurality of periods of the laser pulse train, the spectrometer integrates the LIBS signal produced by this plurality of laser pulses. Hence the intensity of the obtained LIBS spectrum can be greatly improved to increase the signal-to-noise ratio (SNR) and lower the level of detection (LOD).

Systems and methods for imaging in the short wave infrared (SWIR), photodetectors with low dark current and associated circuits for reducing dark currents and methods for generating image information based on data of a photodetector array. A SWIR imaging system may include a pulsed illumination source operative to emit radiation pulses in the SWIR band towards a target resulting in reflected radiation from the target; (b) an imaging receiver including a plurality of Ge PDs operative to detect the reflected SWIR radiation and a controller, operative to control activation of the receiver for an integration time during which the accumulated dark current noise does not exceed the time independent readout noise.

An optical transconductance varistor system having a modulated radiation source configured to provide modulated stimulus, a wavelength converter operably connected to the modulated radiation source to produce a modulated stimulus having a predetermined wavelength, and a wide bandgap semiconductor photoconductive material in contact between two electrodes. The photoconductive material is operably coupled, such as by a beam transport module, to receive the modulated stimulus having the predetermined wavelength to control a current flowing through the photoconductive material when a voltage potential is present across the electrodes.