Abstract: The exemplary embodiments of the present invention include forming a photoconductor thin film on a front surface of a substrate; forming a photoconductor thin film pattern by patterning the photoconductor thin film; and forming a metal electrode on the photoconductor thin film pattern.

Abstract: A terahertz continuous wave generator includes: an optical intensity modulator configured to modulate an optical signal into DSB optical signals; a local oscillator configured to generate a modulation signal for modulating the optical signal inputted to the optical intensity modulator into DSB optical signals; a notch filter configured to filter an optical signal with a specific frequency; an optical fiber amplifier configured to amplify an output signal of the optical intensity modulator; an optical circulator configured to transmit the optical signal inputted to the optical fiber amplifier to the notch filter and transmit the optical signal reflected from the notch filter to an input of the optical intensity modulator; an optical coupler configured to apply the optical signal to the optical intensity modulator; and an OE converter configured to photomix the DSB signals outputted through the notch filter.

Abstract: Provided is a waveguide photomixer in which an absorption layer is selectively etched to reduce a junction area. The waveguide photomixer includes a buffer layer disposed on a substrate, a first clad layer disposed on the buffer layer and formed to have smaller width than that of a top surface of the buffer layer, an absorption layer disposed on the first clad layer and formed to have smaller width than that of a top surface of the first clad layer, a second clad layer disposed on the absorption layer and formed to have greater width than that of a top surface of the absorption layer, a contact layer disposed on the second clad layer, a first electrode unit disposed on the buffer layer where the first clad layer is not disposed, and a second electrode unit disposed on the contact layer.

Abstract: Disclosed is a terahertz transmitter which includes a photonics oscillator configured to generate two optical signals with different wavelength and strong correlation; a modulator configured to modulate the optical signals; a pre-amplifier configured to amplify the modulated optical signals; a photomixer configured to generate a terahertz signal through photomixing of the amplified optical signals; and a post-amplifier configured to amplify the terahertz signal and to transmit the amplified terahertz signal through an antenna.

Abstract: The inventive concept relates to a terahertz receiver. The terahertz receiver of the inventive concept includes a plurality of terahertz detectors detecting signals of terahertz band from received signals; a plurality of optical signal processing parts converting the detected terahertz signals into optical signals; an optical combiner combining the converted optical signals into one optical signal; a photodiode converting the combined optical signal into an electrical signal; and an amplifier amplifying the electrical signal.

Abstract: A field emission pixel includes a cathode on which a field emitter emitting electrons is formed, an anode on which a phosphor absorbing electrons from the field emitter is formed, and a thin film transistor (TFT) having a source connected to a current source in response to a scan signal, a gate receiving a data signal, and a drain connected to the field emitter. The field emitter is made of carbon material such as diamond, diamond like carbon, carbon nanotube or carbon nanofiber. The cathode may include multiple field emitters, and the TFT may include multiple transistors having gates to which the same signal is applied, sources to which the same signal is applied, and drains respectively connected to the field emitters. An active layer of the TFT is made of a semiconductor film such as amorphous silicon, micro-crystalline silicon, polycrystalline silicon, wide-band gap material like ZnO, or an organic semiconductor.

Abstract: Provided are an abrupt MIT device with variable MIT temperature or voltage, an MIT sensor using the abrupt MIT device, and an alarm apparatus and a secondary battery anti-explosion circuit including the MIT sensor. The MIT device includes an abrupt MIT layer undergoing an abrupt MIT at a transition temperature or a transition voltage and at least two electrode layers contacting the abrupt MIT layer. The transition temperature or the transition voltage varies with at least one of factors including a voltage applied to the electrode layers, a temperature, an electromagnetic wave, a pressure, and a gas concentration that affect the abrupt MIT layer. The MIT sensor is a temperature sensor, an infrared sensor, an image sensor, a pressure sensor, a gas-concentration sensor, or a switch. The alarm apparatus includes the MIT sensor and an alarm-signaling unit connected in series with the MIT sensor.

Abstract: A terahertz continuous wave generator includes: an optical intensity modulator configured to modulate an optical signal into DSB optical signals; a local oscillator configured to generate a modulation signal for modulating the optical signal inputted to the optical intensity modulator into DSB optical signals; a notch filter configured to filter an optical signal with a specific frequency; an optical fiber amplifier configured to amplify an output signal of the optical intensity modulator; an optical circulator configured to transmit the optical signal inputted to the optical fiber amplifier to the notch filter and transmit the optical signal reflected from the notch filter to an input of the optical intensity modulator; an optical coupler configured to apply the optical signal to the optical intensity modulator; and an OE converter configured to photomix the DSB signals outputted through the notch filter.

Abstract: A device characteristics measurement method using an all-optoelectronic terahertz photomixing system includes: calculating power of an antenna of a transmitter by adding a matching condition between output impedance of the photomixer and input impedance of the antenna of the transmitter to power of the photomixer of the transmitter; calculating power of an antenna of a receiver based on the power of the antenna of the transmitter; and outputting the power of the antenna of the transmitter and the power of the antenna of the receiver so as to analyze device characteristics of the photomixer and the antenna of the transmitter.

Abstract: The exemplary embodiments of the present invention include forming a photoconductor thin film on a front surface of a substrate; forming a photoconductor thin film pattern by patterning the photoconductor thin film; and forming a metal electrode on the photoconductor thin film pattern.

Abstract: A field emission pixel includes a cathode on which a field emitter emitting electrons is formed, an anode on which a phosphor absorbing electrons from the field emitter is formed, and a thin film transistor (TFT) having a source connected to a current source in response to a scan signal, a gate receiving a data signal, and a drain connected to the field emitter. The field emitter is made of carbon material such as diamond, diamond like carbon, carbon nanotube or carbon nanofiber. The cathode may include multiple field emitters, and the TFT may include multiple transistors having gates to which the same signal is applied, sources to which the same signal is applied, and drains respectively connected to the field emitters. An active layer of the TFT is made of a semiconductor film such as amorphous silicon, micro-crystalline silicon, polycrystalline silicon, wide-band gap material like ZnO, or an organic semiconductor.

Abstract: Provided are a condenser lens-coupled photoconductive antenna device for terahertz wave generation and detection and a fabricating method thereof. A condenser lens-coupled photoconductive antenna device for terahertz wave generation and detection includes a condenser lens, a photoconductive thin film deposited on the condenser lens, and a metal electrode formed on the photoconductive thin film for a photoconductive antenna. In the antenna device, the condenser lens and the photoconductive thin film are coupled to each other.

Abstract: Provided are a terahertz wave transmission and reception (Tx/Rx) module package and method of manufacturing the same. The complete and separate terahertz wave Tx/Rx module package is implemented by simply aligning a silicon ball lens, a photoconductive antenna and a focusing lens, and thus facilitates generation or measurement of a terahertz wave. The terahertz wave Tx/Rx module package and method can remarkably reduce time and cost required to build a terahertz wave generation and measurement system, and simplify and miniaturize the terahertz wave generation and measurement system. In addition, characteristics of a terahertz wave generated by the photoconductive antenna can be simply measured. Furthermore, the terahertz wave Tx/Rx module package can be stored and transported with a photoconductive antenna, a silicon ball lens and a focusing lens kept aligned as they are, and also it is possible to minimize pollution of terahertz wave devices caused by surroundings.

Abstract: Provided is a field emission display (FED) capable of driving on the basis of current and preventing leakage current caused by thin film transistors (TFTs). The FED includes: a plurality of unit pixels including an emission element in which cathode luminescence of a phosphor occurs and a TFT for driving the emission element; a current source for applying a scan signal to each unit pixel; and a voltage source for applying a data signal to each unit pixel. Here, the on-current of the current source is high enough to take care of the load resistance and capacitance of a scan row within a given writing time, and the off-current of the current source is so low that the electron emission of each pixel can be ignored. In addition, the pulse amplitude or pulse width of the data signal applied from the voltage source is changed, and thereby the gray scale of the display is represented.

Abstract: Provided is a lithium secondary battery including a discharge unit capable of delaying or preventing a battery explosion. The lithium secondary battery includes a discharge unit disposed parallel to a battery body. The discharge unit includes a first electrode connected to a positive electrode of the battery body, a second electrode connected to a negative electrode of the battery body, and a discharge material film, disposed between the first electrode and the second electrode, inducing a abrupt discharge above a predetermined temperature. The discharge material film, e.g., a abrupt metal-insulator transition (MIT) material film can induce a abrupt discharge, thereby preventing or delaying a battery explosion.

Abstract: An abrupt MIT (metal-insulator transition) device with parallel MIT material layers is provided. The abrupt MIT device includes a first electrode disposed on a certain region of a substrate, a second electrode disposed so as to be spaced a predetermined distance apart from the first electrode, and at least one MIT material layer electrically connecting the first electrode with the second electrode and having a width that allows the entire region of the MIT material layer to be transformed into a metal layer due to an MIT. Due to this configuration, deterioration of the MIT material layer, which is typically caused by current flowing through the MIT material layer, is less likely to occur.

Abstract: Provided are a temperature sensor using a metal-insulator transition (MIT) device subject to abrupt MIT at a specific temperature and an alarm including the temperature sensor. The abrupt MIT device includes an abrupt MIT thin film and at least two electrode thin films that contacts the abrupt MIT thin film. The abrupt MIT device generates abrupt metal-insulator transition at a specific transition temperature. The alarm includes a temperature sensor comprising an abrupt MIT device, and an alarm signaling device serially connected to the temperature sensor. Accordingly, the alarm can be manufactured to have a simple circuit and be of a small size by including the temperature sensor using an abrupt MIT device.

Abstract: An electron emission device having a high electron emitting rate and a display including the device are provided. The electron emission device using abrupt metal-insulator transition, the device including: a board; a metal-insulator transition (MIT) material layer disposed on the board and divided by a predetermined gap with portions of the divided MIT material layer facing one another; and electrodes connected to each of the portions of the divided metal-insulator transition material layer for emitting electrons to the gap between the portions of the divided metal-insulator transition material layer.

Abstract: Provided are a low-voltage noise preventing circuit using an abrupt metal-insulator transition (MIT) device which can effectively remove a noise signal with a voltage less than a rated signal voltage. The abrupt MIT device is serially connected to the electrical and/or electronic system to be protected from the noise signal, and is subject to abrupt MIT at a predetermined voltage. Accordingly, low-voltage noise can be effectively removed.

Abstract: A switching field effect transistor includes a substrate; a Mott-Brinkman-Rice insulator formed on the substrate, the Mott-Brinkman-Rice insulator undergoing abrupt metal-insulator transition when holes added therein; a dielectric layer formed on the Mott-Brinkman-Rice insulator, the dielectric layer adding holes into the Mott-Brinkman-Rice insulator when a predetermined voltage is applied thereto; a gate electrode formed on the dielectric layer, the gate electrode applying the predetermined voltage to the dielectric layer; a source electrode formed to be electrically connected to a first portion of the Mott-Brinkman-Rice insulator; and a drain electrode formed to be electrically connected to a second portion of the Mott-Brinkman-Rice insulator.