The invention relates to a modulatable infrared emitter comprising an aperture structure, a structured micro-heating element, and an actuator, wherein the aperture structure and the structured micro-heating element are movable relative to each other in parallel planes by means of the actuator to modulate the intensity of emitted infrared radiation. The invention further relates to methods of manufacturing the infrared emitter, a method of modulating emission of infrared radiation using the infrared emitter, and preferred uses of the infrared emitter. In further aspects the invention relates to a system comprising the infrared emitter and a control device for regulating the actuator.

A photoconductive device that includes a semiconductor substrate, an antenna assembly, and a photoconductive assembly with one or more plasmonic contact electrodes. The photoconductive assembly can be provided with plasmonic contact electrodes that are arranged on the semiconductor substrate in a manner that improves the quantum efficiency of the photoconductive device by plasmonically enhancing the pump absorption into the photo-absorbing regions of semiconductor substrate. In one exemplary embodiment, the photoconductive device is arranged as a photoconductive source and is pumped at telecom pump wavelengths (e.g., 1.0-1.6 μm) and produces milliwatt-range power levels in the terahertz (THz) frequency range.

Described herein are optical sensing devices for photonic integrated circuits (PICs). A PIC may comprise a plurality of waveguides formed in a silicon on insulator (SOI) substrate, and a plurality of heterogeneous lasers, each laser formed from a silicon material of the SOI substrate and to emit an output wavelength comprising an infrared wavelength. Each of these lasers may comprise a resonant cavity included in one of the plurality of waveguides, and a gain material comprising a non-silicon material and adiabatically coupled to the respective waveguide. A light directing element may direct outputs of the plurality of heterogeneous lasers from the PIC towards an object, and one or more detectors may detect light from the plurality of heterogeneous lasers reflected from or transmitted through the object.

A semiconductor-based light emitting platform (LEP) comprising a heated blackbody radiator wherein the light emitting platform is thermally isolated by nanowires having ultra-low thermal conductivity. In embodiments, the pixel is structured for broadband emission with a platform comprising an infrared surface structured for high emissivity within a broadband wavelength range. In other embodiments radiation is confined to a limited bandwidth by metamaterial and other resonant filters. In embodiments, the internal efficiency of the LEP configured for broadband operation can be higher compared with an LED.

The present disclosure describes broadband optical emission sources that include a stack of semiconductor layers, wherein each of the semiconductor layers is operable to emit light of a different respective wavelength; a light source operable to provide optical pumping for stimulated photon emission from the stack; wherein the semiconductor layers are disposed sequentially in the stack such that a first one of the semiconductor layers is closest to the light source and a last one of the semiconductor layers is furthest from the light source, and wherein each particular one of the semiconductor layers is at least partially transparent to the light generated by the other semiconductor layers that are closer to the light source than the particular semiconductor layer. The disclosure also describes various spectrometers that include a broadband optical emission device, and optionally include a tuneable wavelength filter operable to allow a selected wavelength or narrow range of wavelengths to pass through.

An embodiment of the present invention provides a continuous-wave terahertz generation and detection device using a photomixing technique, the device including: first and second light source units configured to output continuous-wave laser light sources, which have single wavelength and different frequencies, to generate optical signals; a first electro-optic phase modulator configured to shift a frequency of the optical signal generated by the first light source unit, and a second electro-optic phase modulator configured to shift a frequency of the optical signal generated by the second light source unit; a first optical amplifier configured to receive and amplify the optical signal whose frequency is shifted by the first electro-optic phase modulator and the optical signal generated by the second light source unit, and a second optical amplifier configured to receive and amplify the optical signal whose frequency is shifted by the second electro-optic phase modulator and the optical signal generated by the first light source unit; an opto-electronic converter configured to convert the optical signal amplified by the first optical amplifier into a terahertz wave; a photomixer configured to mix the optical signal amplified by the second optical amplifier and the terahertz wave generated by the opto-electronic converter and convert the mixed signal into an electrical signal; a photodetector configured to combine the optical signals transferred from the first and second optical amplifiers and convert the combined optical signal into an electrical signal; and a filter unit configured to filter the electrical signal passing through the photodetector, wherein the electrical signal obtained through the photodetector is compared with the electrical signal obtained by the photomixer, and phase noise having the same frequency is removed.

A thermal emitter includes a freestanding membrane supported by a substrate, wherein the freestanding membrane includes in a lateral extension a center section, a conductive intermediate section and a border section, wherein the conductive intermediate section laterally surrounds the center section and is electrically isolated from the center section, the conductive intermediate section including a conductive semiconductor material that is encapsulated in an insulating material, wherein the border section at least partially surrounds the intermediate section and is electrically isolated from the conductive intermediate section, and wherein a perforation is formed through the border section.

Systems and methods for determining one or more properties of a sample are disclosed. The systems and methods disclosed can be capable of measuring along multiple locations and can reimage and resolve multiple optical paths within the sample. The system can be configured with one-layer or two-layers of optics suitable for a compact system. The optics can be simplified to reduce the number and complexity of the coated optical surfaces, et al. on effects, manufacturing tolerance stack-up problems, and interference-based spectroscopic errors. The size, number, and placement of the optics can enable multiple simultaneous or non-simultaneous measurements at various locations across and within the sample. Moreover, the systems can be configured with an optical spacer window located between the sample and the optics, and methods to account for changes in optical paths due to inclusion of the optical spacer window are disclosed.

A measurement system is provided with an array of laser diodes with one or more Bragg reflectors. At least a portion of the light generated by the array is configured to penetrate tissue comprising skin. A detection system configured to: measure a phase shift, and a time-of-flight, of at least a portion of the light from the array of laser diodes reflected from the tissue relative to the portion of the light generated by the array; generate one or more images of the tissue; detect oxy- or deoxy-hemoglobin in the tissue; non-invasively measure blood in blood vessels within or below a dermis layer within the skin; measure one or more physiological parameters based at least in part on the non-invasively measured blood; and measure a variation in the blood or physiological parameter over a period of time.

An active remote sensing system is provided with an array of laser diodes that generate light directed to an object having one or more optical wavelengths that include at least one near-infrared wavelength between 600 nanometers and 1000 nanometers. One of the laser diodes pulses at a modulation frequency between 10 Megahertz and 1 Gigahertz and has a phase associated with the modulation frequency. A detection system includes a photo-detector, a lens, a spectral filter at an input to the photo-detector, and a processor that processes digitized signals received from the photo-detector to generate an output signal. The detection system uses a lock-in technique that synchronizes pulsing the one laser diode. The active remote sensing system is configured to be mounted on a vehicle or an airborne platform to provide distance information based on a time-of-flight measurement.