Abstract: Disclosed herein is a photomixer and method of manufacturing the photomixer which can fundamentally solve the existing restrictive factors of a PCA and a photomixer which are core parts of a conventional broadband terahertz spectroscopy system. The presented photomixer includes an active layer formed on a top surface of a substrate, the active layer being formed on an area on which light is incident, and a thermal conductive layer formed on the top surface of the substrate, the thermal conductive layer being formed on an area other than the area on which light is incident. The active layer is formed to have a mesa cross section, and the thermal conductive layer is regrown on an area other than the area on which light is incident using an MOCVD method, and has a flattened surface.

Abstract: Provided is a broadband photomixer technology that is a core to generate continuous frequency variable and pulsed terahertz waves. It is possible to enhance light absorptance by applying the transmittance characteristic of a 2D light crystal structure and it is possible to increase the generation efficiency of terahertz waves accordingly. Moreover, it is possible to implement a wide area array type terahertz photomixer by applying an interdigit structure and spatially properly arranging a light crystal structure having various cycles. Accordingly, it is possible to solve difficulty in thermal characteristic and light alignment by mitigating the high light density of a light absorption unit and low photoelectric conversion efficiency is drastically improved. In addition, the radiation pattern of terahertz waves may be electrically controlled through the present invention.

Abstract: Provided is a terahertz wave generating/detecting apparatus and a method for manufacturing the same. The terahertz wave generating/detecting apparatus includes; a substrate having an active region and a transmitting region; a lower metal layer extending in a first direction on the active region and the transmitting region of the substrate; a graphene layer disposed on the lower metal layer on the active region; and upper metal layers extending in the first direction on the graphene layer of the active region and the substrate in the transmission region, wherein a terahertz wave is generated or amplified by a surface plasmon polariton that is induced on a boundary surface between the graphene layer and the lower metal layer by beated laser light applied to the graphene layer and the metal layer.

Abstract: Disclosed is a rectifier capable of performing a high speed rectifying operation, and includes: a first semiconductor layer; a second semiconductor layer; and a third semiconductor layer, in which the first semiconductor layer and the third semiconductor layer are formed of semiconductor layers having the same type, and the second semiconductor layer is formed between the first semiconductor layer and the third semiconductor layer, is formed of a semiconductor layer having a different type from that of the first semiconductor layer and the third semiconductor layer, and is formed in graded doped state.

Abstract: A terahertz wave generating module includes a bidirectional light source which provides a first dual-mode beam in a first direction and a second dual-mode beam in a second direction; a forward lens unit which focuses the first dual-mode beam; a photomixer unit which converts the first dual-mode beam focused by the forward lens unit into a terahertz wave; a backward lens unit which focuses the second dual-mode beam; and a light output unit which uses the second dual-mode beam focused by the backward lens unit as a light signal, wherein the bidirectional light source, the forward lens unit, the photomixer unit, the backward lens unit, and the light output unit are integrated in a housing.

Abstract: Disclosed is a photomixer for generating and detecting a terahertz continuous wave, including: an optical conductor to which beating light is incident; and a plurality of antenna feeding electrodes formed on both side surfaces of the optical conductor, and configured to receive a current of a terahertz frequency.

Abstract: Provided herein is terahertz continuous wave emitting device having: a plurality of laser light sources generating a plurality of laser lights; and an absorption area formed between the plurality of laser light sources in order to adjust interaction of the plurality of laser lights, wherein the absorption area is configured to have a photo diode, an antenna integrated into the photo diode.

Abstract: Provided are a THz-wave generation/detection module and a device including the same, which increase heating efficiency and are miniaturized. The module includes a photomixer chip, a lens, a PCB, and a package. The photomixer chip includes an active layer, an antenna, and a plurality of electrode pads. The lens is disposed on the photomixer chip. The PCB includes a plurality of solder balls connected to the electrode pads, under the photomixer chip. The package surrounds a bottom and side of the PCB, and dissipates heating of the active layer, which is transferred from the electrode pad of the photomixer chip to the PCB, to outside.

Abstract: Disclosed is a lower track for mounting rubber pads on a track shoe to be attachable and detachable after assembling a steel plate which is adhered with divisionally formed rubber pads as a single unit without additionally perforating coupling through-holes in the track shoe when the rubber pad which forms the lower track and the track shoe which is formed of a metal material are coupled.

Abstract: Provided is a broadband photomixer technology that is a core to generate continuous frequency variable and pulsed terahertz waves. It is possible to enhance light absorptance by applying the transmittance characteristic of a 2D light crystal structure and it is possible to increase the generation efficiency of terahertz waves accordingly. Moreover, it is possible to implement a wide area array type terahertz photomixer by applying an interdigit structure and spatially properly arranging a light crystal structure having various cycles. Accordingly, it is possible to solve difficulty in thermal characteristic and light alignment by mitigating the high light density of a light absorption unit and low photoelectric conversion efficiency is drastically improved. In addition, the radiation pattern of terahertz waves may be electrically controlled through the present invention.

Abstract: Provided are a dual mode semiconductor laser and a terahertz wave apparatus using the same. The dual mode semiconductor laser includes a distributed feedback laser structure section including a first diffraction grating on a substrate and a distributed Bragg reflector laser structure section including a second diffraction grating on the substrate. A first wavelength oscillated by the distributed feedback laser structure section and a second wavelength oscillated by the distributed Bragg reflector laser structure section are different from each other, and the distributed feedback laser structure section and the distributed Bragg reflector laser structure section share the same gain medium with each other.

Abstract: An optical device may include first and second lasers generating first and second laser beams; and a photo detector detecting the first and second laser beams. The optical detector comprises a substrate, a first impurity layer on the substrate, an absorption layer on the first impurity layer and a second impurity layer on the absorption layer. The absorption layer generates a terahertz by a beating of the first and second laser beams and has a thickness of less than 0.2 ?m.

Abstract: Provided is a terahertz wave generating/detecting apparatus and a method for manufacturing the same. The terahertz wave generating/detecting apparatus includes; a substrate having an active region and a transmitting region; a lower metal layer extending in a first direction on the active region and the transmitting region of the substrate; a graphene layer disposed on the lower metal layer on the active region; and upper metal layers extending in the first direction on the graphene layer of the active region and the substrate in the transmission region, wherein a terahertz wave is generated or amplified by a surface plasmon polariton that is induced on a boundary surface between the graphene layer and the lower metal layer by beated laser light applied to the graphene layer and the metal layer.

Abstract: The inventive concept relates to a beating signal monitoring module and a terahertz wave generation device and an optical signal monitoring device that including the beating signal monitoring module. The beating signal monitoring module includes a nonlinear unit generating an optical signal including a FWM light in response to a beating signal generated from a first light and a second light; a filter unit separating the FWM light from the optical signal and outputting the separated FWM light; and a monitoring unit monitoring the beating signal using the separated FWM light. The beating signal monitoring module and a terahertz wave generation device and an optical signal monitoring device that including the beating signal monitoring module can effectively monitor a beating signal being generated by two lasers using a Four Wave Mixing signal.

Abstract: A terahertz wave generating module includes a bidirectional light source which provides a first dual-mode beam in a first direction and a second dual-mode beam in a second direction; a forward lens unit which focuses the first dual-mode beam; a photomixer unit which converts the first dual-mode beam focused by the forward lens unit into a terahertz wave; a backward lens unit which focuses the second dual-mode beam; and a light output unit which uses the second dual-mode beam focused by the backward lens unit as a light signal, wherein the bidirectional light source, the forward lens unit, the photomixer unit, the backward lens unit, and the light output unit are integrated in a housing.

Abstract: A method of manufacturing a frequency tunable terahertz transceiver including two separate distributed feedback lasers manufactured in one substrate, includes forming a lower clad layer on the substrate, forming an active layer on the lower clad layer, forming an upper clad layer on the active layer. And interposing first and second diffraction grating layers between the upper clad layers. A diffraction grating is manufactured by etching the first and second diffraction grating layers. The active layer is integrated into a passive waveguide. An electrode is formed on the upper clad layer.

Abstract: Provided are a frequency tunable terahertz transceiver and a method of manufacturing a dual wavelength laser. The frequency tunable terahertz transceiver includes: a dual wavelength laser including two distributed feedback lasers that are manufactured in one substrate and output optical signals of respectively different wavelengths; and an optical device receiving the outputted optical signals to generate a terahertz wave.

Abstract: Disclosed is a terahertz wave generator which includes a first light source outputting a first light having a first frequency; a second light source outputting a second light having a second frequency different from the first frequency; a second harmonic generation unit performing second harmonic conversion on the first and second lights to generate a third light and a fourth light; and a photomixer converting a mixing light of the third and fourth lights into a terahertz wave alternating signal and outputting a terahertz wave.

Abstract: Disclosed herein is an interconnection apparatus and method using terahertz waves. The interconnection apparatus using terahertz waves according to the present invention includes a first terahertz wave generation unit for generating a first transmission terahertz wave, a center frequency of which is a first center frequency, using photomixing. A second terahertz wave generation unit generates a second transmission terahertz wave, a center frequency of which is a second center frequency different from the first center frequency. A first terahertz wave detection unit detects a first reception terahertz wave corresponding to the first transmission terahertz wave. A second terahertz wave detection unit detects a second reception terahertz wave corresponding to the second transmission terahertz wave.

Abstract: Disclosed is a terahertz wave generator which includes a dual mode semiconductor laser device configured to generate at least two laser lights having different wavelengths and to beat the generated laser lights; and a photo mixer formed on the same chip as the dual mode semiconductor laser device and to generate a continuous terahertz wave when excited by the beat laser light.