Abstract: A method of operating a wavelength swept source apparatus includes generating a single mode light, and generating a basic optical comb including light rays having identical frequency differences with adjacent light rays by modulating the generated single mode light. The method further includes generating other optical combs that include the same number of light rays as that of light rays of the optical comb that has a frequency band different from that of the basic optical comb, and is distributed in a frequency band wider than that in which the basic optical comb is distributed, by modulating the light rays of the basic optical comb. The light rays of the basic optical comb and the light rays included in the other optical combs are sequentially emitted according to frequencies of the light rays of the basic optical comb and the light rays included in the other optical combs.

Abstract: A method of operating a wavelength swept source apparatus includes generating a single mode light, and generating a basic optical comb including light rays having identical frequency differences with adjacent light rays by modulating the generated single mode light. The method further includes generating other optical combs that include the same number of light rays as that of light rays of the optical comb that has a frequency band different from that of the basic optical comb, and is distributed in a frequency band wider than that in which the basic optical comb is distributed, by modulating the light rays of the basic optical comb. The light rays of the basic optical comb and the light rays included in the other optical combs are sequentially emitted according to frequencies of the light rays of the basic optical comb and the light rays included in the other optical combs.

Abstract: Provided herein is a distributed bragg reflector ridge laser diode that is capable of easily embodying a diffraction grating and that minimizes an optical absorption effect on a DBR area, and a fabricating method thereof, the distributed bragg reflector ridge laser diode including a lower clad layer formed on top of a substrate; an active core zone formed on top of the lower clad layer; a plurality of ridge wave guides formed on top of the active core zone such that they are spaced from one another and extend in an axial direction; and a diffraction grating formed on top of the active core zone and between the plurality of ridge wave guides.

Abstract: Provided are a spot size converter and a method of manufacturing the spot size converter. The method includes stacking a lower clad layer, a core layer, and a first upper clad layer on a substrate, tapering the first upper clad layer and the core layer in a first direction on a side of the substrate, forming a waveguide layer on the first upper clad layer and the lower clad layer, and etching the waveguide layer, the first upper clad layer, the core layer, and the lower clad layer such that the waveguide layer is wider than a tapered portion of the core layer on the side of the substrate and has the same width as that of the core layer on another side of the substrate.

Abstract: Provided are a wavelength swept source apparatus and a method for controlling thereof. According to the provided apparatus and method, single mode light is generated, a basic optical comb is generated by modulating the generated single mode light, and a plurality of optical combs having different a frequency band from that of the basic optical comb is generated by modulating the plurality of light rays. The plurality of light rays and light rays included in the plurality of optical combs are sequentially emitted according to frequencies of the plurality of light rays and the light rays included in the plurality of optical combs. A value of a control variable is adjusted based on a characteristic of the generated single mode light, the plurality of light rays, the light rays included in the plurality of optical combs, and the emitted light rays.

Abstract: Provided are a wavelength swept source apparatus and a method for operating thereof. According to the provided apparatus and method, single mode light is generated, a basic optical comb including a plurality of light rays having identical frequency differences with adjacent light rays is generated by modulating the generated single mode light, and a plurality of optical combs, that includes same number of light rays as the plurality of light rays, has a different frequency band from that of the basic optical comb, and is distributed in a wider frequency band than that in which the basic optical comb is distributed, is generated by modulating the plurality of light rays. The plurality of light rays and light rays included in the plurality of optical combs are sequentially emitted according to frequencies of the plurality of light rays and the light rays included in the plurality of optical combs.

Abstract: Provided is a distributed feedback-laser diode (DFB-LD) and manufacturing method thereof. The DFB-LD includes a substrate; a lower clad layer having a grating on the substrate; an active waveguide extended in a first direction on the lower clad layer; an upper clad layer on the active waveguide; a signal pad on the upper clad layer; and at least one ground pad spaced apart from the active waveguide, the upper clad layer, and the signal pad in a second direction crossing the first direction, the at least one ground pad being coupled to the lower clad layer.

Abstract: Provided is a method of manufacturing a ridge waveguide type semiconductor laser diode, the method including sequentially forming, on a substrate, a lower clad layer, an active layer, a first upper clad layer, and a second upper clad layer; forming an insulating mask on the second upper clad layer; wet-etching the second upper clad layer by using the insulating mask to form channels passing through the second upper clad layer and a ridge between the channels; and performing dry-etching by using the insulating mask to form trenches that are extended from the channels and pass through the first upper clad layer.

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: 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: Provided is a multi-wavelength optical source generator. The multi-wavelength optical source generator includes: a gain part generating a plurality of lights through a plurality of gain waveguides; a reflective part transmitting or reflecting lights provided from each of the plurality of gain waveguides according to a wavelength; and a multiplexing part multiplexing a plurality of lights transmitted and outputted through the reflective part.

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.

Abstract: Provided are a spot size converter and a method of manufacturing the spot size converter. The method includes stacking a lower clad layer, a core layer, and a first upper clad layer on a substrate, tapering the first upper clad layer and the core layer in a first direction on a side of the substrate, forming a waveguide layer on the first upper clad layer and the lower clad layer, and etching the waveguide layer, the first upper clad layer, the core layer, and the lower clad layer such that the waveguide layer is wider than a tapered portion of the core layer on the side of the substrate and has the same width as that of the core layer on another side of the substrate.

Abstract: Provided is a multichannel transmitter optical module which includes a plurality of light source units configured to generate light, a plurality of an electro-absorption modulators (EAMs) configured to modulate the generated light to an optical signal through a radio frequency (RF) signal, a plurality of RF transmission lines configured to apply the RF signal to the EAMs, and a combiner configured to combine the modulated optical signal. The RF transmission lines are connected to the EAMs in a traveling wave (TW) electrode manner. The multichannel transmitter optical module has alleviated crosstalk and is compactly integrated to have a small size.

Abstract: Provided are a distributed feedback laser diode and a manufacturing method thereof. The distributed feedback laser diode includes a first area having a first grating layer disposed in a longitudinal direction, a second area disposed adjacent to the first area and having a second grating layer disposed in the longitudinal direction, and an active layer disposed over the first and second areas. Coupling coefficients of the first and second grating layers are made different in the first and second areas by a selective area growth method. The distributed feedback laser diode includes grating layers each having an asymmetric coefficient and is implemented within an optimal range capable of obtaining both a high front facet output and stable single mode characteristics. Thus, high manufacturing yield and low manufacturing cost can be achieved.

Abstract: Provided is a laser device. In the laser device, an active layer is connected to a stem core of a 1×2 splitter on a substrate, a first diffraction grating is coupled to a first twig core of the 1×2 splitter, and a second diffraction grating is coupled to a second twig core of the 1×2 splitter. An active layer-micro heater is designed to supply heat to the active layer. First and second micro heaters are designed to supply heats to the first and second diffraction gratings, respectively, thereby varying a Bragg wavelength.

Abstract: Provided is a multi-wavelength optical source generator. The multi-wavelength optical source generator includes: a gain part generating a plurality of lights through a plurality of gain waveguides; a reflective part transmitting or reflecting lights provided from each of the plurality of gain waveguides according to a wavelength; and a multiplexing part multiplexing a plurality of lights transmitted and outputted through the reflective part.

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 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.

Abstract: Provided is an optical comb generator including a light source, a first waveguide region, a modulation region, and a second waveguide region. The light source is configured to output single-mode light. The first waveguide region divides an output of the light source into first light and second light. The modulation region includes a first modulator and a second modulator modulating the first light and the second light respectively. The second waveguide region combines outputs of the first modulator and the second modulator to output an optical comb. Here, the first modulator and the second modulator respectively include a first quantum well and a second quantum well having an asymmetric structure with respect to each other. The light source, the first waveguide region, the modulation region, and the second waveguide region are integrated into one substrate.