679 results about "Optical pumping" patented technology

Optoelectronic devices are provided that incorporate quantum dots as the electroluminescent layer in an inorganic wide-bandgap heterostructure. The quantum dots serve as the optically active component of the device and, in multilayer quantum dot embodiments, facilitate nanoscale epitaxial lateral overgrowth (NELOG) in heterostructures having non-lattice matched substrates. The quantum dots in such devices will be electrically pumped and exhibit electroluminescence, as opposed to being optically pumped and exhibiting photoluminescence. There is no inherent “Stokes loss” in electroluminescence thus the devices of the present invention have potentially higher efficiency than optically pumped quantum dot devices. Devices resulting from the present invention are capable of providing deep green visible light, as well as, any other color in the visible spectrum, including white light by blending different sizes and compositions of the dots and controlling manufacturing processes.

An organic vertical cavity laser light producing device (10) comprises a substrate (20). A plurality of laser emitters (200) emits laser light in a direction orthogonal to the substrate. Each laser emitter within the plurality of laser emitters has a first lateral mode structure in a first axis orthogonal to the laser light direction and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and the first axis. Each laser emitter comprises a first mirror provided on a top surface of the substrate (20) and is reflective to light over a predetermined range of wavelengths. An organic active region (40) produces laser light (350). A second mirror is provided above the organic active region and is reflective to light over a predetermined range of wavelengths. A pumping means excites the plurality of laser emitters.

The present invention provides a method and apparatus for making atomic clocks or atomic magnetometers as self-modulated laser systems based on the physics of push-pull optical pumping. An atomic vapor cell is required to be in the laser cavity. With proper conditions, spontaneous push-pull optical pumping can occur inside the laser cavity. This causes the laser beam to be modulated at hyperfine-resonance frequency. With a fast photodetector, the modulated laser signal can be converted into the electrical signal, which serves as the atomic clock ticking signal or magnetometer signal. The self-modulated laser system does not use any local oscillator and the microwave circuit to lock the oscillator frequency to the hyperfine-resonance frequency, and therefore can consume less power and become more compact than conventional systems. This invention will benefit applications of time measurements and magnetic-field measurements.

A hub for use in a passive optical network (PON) includes a transmission fiber on which an information-bearing optical signal is received, a double-cladded, rare-earth doped fiber located along the transmission fiber for imparting gain to the information-bearing optical signal, and a combiner having an output coupled to the transmission fiber and a plurality of inputs. The output is coupled to the transmission fiber such that optical energy at pump energy wavelengths but not signal wavelengths are communicated therebetween. At least one pump source is optically coupled to one of the inputs of the combiner for providing optical pump energy to the double-cladded, rare-earth doped fiber. An optical splitter is also provided. The optical splitter has an input coupled to the transmission fiber for receiving an amplified, information-bearing optical signal and a plurality of outputs for directing portions of the amplified, information-bearing optical signal to remote nodes in the PON.

An active protection system comprising an ultrawideband radar for threat detection, an optical tracker for precision threat position measurement, and a high powered laser for threat kill or mitigation. The uwb radar may use a sparse array antenna and may also utilize Doppler radar information. The high powered laser may be of the optically pumped solid state type and in one embodiment may share optics with the optical tracker. In one embodiment, the UWB radar is used to focus the high power laser. Alternative interceptor type kill mechanisms are disclosed. In a further embodiment, the kill mechanism may be directed to the source of the threat.

The present invention addresses the problem of stabilizing signals in magnetic field measurement using optical pumping. In order to solve the problem, disclosed is a light source apparatus (10) that is characterized in having: a light intensity fluctuation detection circuit (130) that detects intensity fluctuation of light outputted from a laser output unit (11); and an acousto-optic modulator (121) that corrects light intensity on the basis of light intensity fluctuation detected by means of the light intensity fluctuation detection circuit (130) such that the light intensity is constant Furthermore, a magnetic field measuring apparatus of the present invention is characterized in having: one sensor unit that passes therethrough light outputted from a light source unit: and a signal control processor that eliminates the light intensity fluctuation on the basis of two lights passed through the sensor unit.

A semiconductor light source is disclosed comprising a substrate, lower and upper claddings, a waveguide region with imbedded active area, and electrical contacts to provide voltage necessary for the wavelength tuning. The active region includes single or several heterojunction periods sandwiched between charge accumulation layers. Each of the active region periods comprises higher and lower affinity semiconductor layers with type-II band alignment. The charge carrier accumulation in the charge accumulation layers results in electric field build-up and leads to the formation of generally triangular electron and hole potential wells in the higher and lower affinity layers. Nonequillibrium carriers can be created in the active region by means of electrical injection or optical pumping. Radiative recombination occurs between the electrons and holes, accumulated in the ground states of the triangular potential wells formed in the high- and low-affinity layers of each active region periods. The ground state energy in the triangular wells and the radiation wavelength can be tuned by changing the voltage drop across the active region.

The invention provides an inertia and magnetic field integration measuring method based on an SERF (spin-exchange-relaxation-free) atomic spin effect. The inertia and magnetic field integration measuring method based on the SERF atomic spin effect comprises the following steps: firstly establishing an overall model for the inertia and magnetic field integration measurement; secondly, manufacturing a measurement sensing unit, and carrying out high-frequency alternating current non-magnetic electric heating; starting a driving laser (z-axis) for carrying out optical pumping on the sensing unit; and emitting a detection laser (x-axis) in a direction vertical to the z-axis; thirdly, carrying out driving magnetic compensation through a three-dimensional magnetic compensation coil so as to counteract a magnetic field of the outside world; fourthly, carrying out azimuth alignment on a main magnetic field and the driving laser and hyperpolarization nucleon self-spin so as to realize the nuclear spin-electron spin strong coupling; fifthly, extracting the information of the atomic spin precession movement in the detection laser by adopting a closed-loop faraday modulation detection method, and obtaining inertia angular speed information; and finally, obtaining the current value of a compensation signal of the magnetic field, and calculating to obtain the information of the current magnetic field. The inertia and magnetic field integration measuring method based on the SERF atomic spin effect has the characteristics of high measurement accuracy and strong autonomy.

A method for operating an extracavity frequency-converted solid-state laser for performing a laser processing operation is disclosed. The laser has a laser-resonator including an optically-pumped gain-medium. The resonator is configured to compensate for a predetermined range of thermal lensing in the gain-medium. An optically-nonlinear crystal located outside the resonator converts fundamental laser radiation delivered by the resonator into frequency converted radiation. The laser processing operation is performed by a train of pulses of the frequency-converted radiation having sufficient power to perform the processing operation. The power of frequency-converted radiation is dependent on delivery parameters of the laser radiation from the laser-resonator. The laser is operated in a manner which provides that the resonator delivers effectively the same average power of fundamental laser radiation before and during the laser processing operation. This provides that thermal-lensing in the gain-medium is within the predetermined range before and during a laser processing operation. Delivery parameters of the laser radiation before and during the processing operation are varied such that power of frequency-converted radiation generated before the processing operating is insufficient to perform a laser processing operation.

An optically pumped magnetometer having a single optical axis using atomic electron spin or nuclear spin includes a detection unit configured to detect an angle of a polarization plane of probe light having components of linear polarization and a modulation unit configured to apply a modulation to the angle of the polarization plane of the probe light having the components of linear polarization. The modulation unit is configured to control an offset in applying the modulation to the angle of the polarization plane of the probe light having the components of linear polarization according to the angle of the polarization plane of the probe light detected by the detection unit.

An optically pumped semiconductor laser includes an active ring-resonator having two or more optically pumped semiconductor (OPS) structures each including a mirror-structure and a multilayer gain-structure. The mirror-structures serve as fold mirrors for the resonator axis. An optically nonlinear crystal may be included in the ring-resonator for generating second-harmonic radiation from fundamental radiation generated in the resonator. Another optically nonlinear crystal may be provided for generating third-harmonic or fourth-harmonic radiation from the second-harmonic radiation. In one example, including a third-harmonic generating crystal, a passive ring-resonator partially coaxial with the active ring-resonator is provided for circulating second-harmonic radiation to provide resonant amplification of the second-harmonic radiation for enhancing third-harmonic conversion. Apparatus for automatically maintaining the passive ring-resonator in a resonant condition for the second-harmonic radiation is disclosed.

A method is disclosed for varying a pulse repetition rate of a passively q-switched laser while maintaining other characteristics of the laser radiation. The laser is optically pumped with a sequence of pump pulses which includes alterations between non-zero power levels and is characterized by two adjustable parameters. By simultaneously changing the adjustable parameters, the pulse repetition rate of the laser can be changed while maintaining the laser pulse energy, divergence of the pulsed laser radiation, and optical spectrum of the pulsed laser radiation at constant levels. In one embodiment, the sequence of pump pulses includes pump power offset which magnitude and/or duration is adjusted when the laser repetition rate is changed.

A laser system includes an optically pumped laser resonator that produces a fundamental-wavelength beam. A temperature-tuned frequency converter outside the laser resonator converts a portion of the fundamental-wavelength beam to a frequency-converted beam. The frequency converter includes at least one temperature-tuned optically nonlinear crystal. The power and position of the frequency-converted beam are dependent on the temperature of the optically nonlinear crystal and the optical pumping power. The power and position of the frequency-converted beam are monitored. The temperature of the optically nonlinear crystal is adjusted to maintain the frequency-converted beam at a predetermined position. The optical pump power is adjusted to maintain the power of the frequency-converted beam at a predetermined level.

The invention concerns a method for the hyperpolarisation of ¹³C nuclear spin in a diamond, comprising an optical pumping step, in which colour centre electron spins in the diamond are optically pumped. The method further comprises a transfer step in which the polarisation of a long-lived state of the colour centre electron spins is transferred to ¹³C nuclear spins in the diamond via a long-range interaction.

An optical pumping magnetometer is provided that is capable of improving the response of the magnetometer with respect to a magnetic field that varies with a period shorter than the transverse relaxation time of electron spin of an alkali metal atom.

A fiber amplifier module for amplifying a signal pulse includes an optically pumped double-pass fiber amplifier in which a fiber Bragg grating reflects an amplified pulse in between the first and second amplification passes, and transmits most forward-propagating amplified spontaneous emission (ASE) generated by the optical pumping. The reflected amplified pulse from the double-pass amplifier, and reverse-propagating ASE generated by the optical pumping are reflected from another fiber Bragg grating that again reflects the amplified pulse and transmits most of the ASE. The twice-reflected amplified pulse can be delivered from the amplifier as an output pulse or passed to another amplifier module for further amplification. The amplifier fiber is operated in a saturated or near saturated mode. This reduces amplification of any portion of the forward-propagating ASE that is reflected into reverse propagation by the fiber Bragg grating of the double-pass amplifier.