Abstract:
A superconducting thermal detector (bolometer) of THz (sub-millimeter) wave radiation based on sensing the change in the amplitude or phase of a resonator circuit, consisting of a capacitor (Csh) and a superconducting temperature dependent inductor where the said inductor is thermally isolated from the heat bath (chip substrate) by micro-suspensions. The bolometer design includes a thin film inductor located on the membrane, a single or/and multi-layered thin film capacitor, and a thin film absorber of incoming radiation. The bolometer design can also include a lithographic antenna with antenna termination and/or a back reflector beneath the membrane for optimal wavelength detection by the resonance circuit. The superconducting thermal detector (bolometer) and arrays of these detectors operate in a temperature range from 1 Kelvin to 10 Kelvin.
Abstract:
The invention relates to a bolometer element, a bolometer cell, a bolometer camera, and a method for reading a bolometer cell. The bolometer cell comprises several bolometer elements. Each bolometer element comprises a first bolometer having a first heating resistance for sensing radiation power acting on the element, and a second bolometer having a second heating resistance, and in each bolometer element the first and second bolometers are electrically connected to each other in such a way that the heating resistance (611) of the first bolometer can be biased with the aid of a voltage through the heating resistance of the second bolometer in order to amplify the radiation power detected with the aid of the connection. With the aid of the invention, it is possible to implement an extremely sensitive bolometer camera.
Abstract:
A radiation detecting array 10 has a frequency domain architecture wherein incident radiation is imaged in parallel by an array of radiation detectors 12-16. Each radiation detector has an associated amplitude to frequency conversion device 18-22 for providing output signals wherein the output of each photodetector is represented as a frequency within a uniquely identified band of frequencies, the specific frequency being a function of the output signal amplitude of the photodetector. The readout of one or more selected detectors is accomplished by providing a swept frequency band or bands associated with the desired detector or detectors and mixing the detector frequencies with the swept band. The frequency representing the photodetector output may be input directly to a low dispersion transmission line 30. The unit cells may include radiation detectors comprised of superconducting material and also superconducting components that inherently manifest current or voltage to frequency conversion characteristics in accordance with the Josepson effect. An array having high temperature superconducting components includes photodetectors 60, associated voltage to frequency convertors 64 and a transmission line 70 integrated upon a common substrate.
Abstract:
A system and method for characterizing incident ions are provided. The method includes positioning a transmission line detector to receive incident ions, the transmission line detector comprising a superconducting meandering wire defining a detection area for incident ions, and applying a bias current to the transmission line detector. The method also includes detecting a first signal produced in the transmission line detector due to an ion impacting the detection area, and detecting a second signal produced in the transmission line detector due to the ion impacting the detection area. The method further includes analyzing the first signal and the second signal to characterize the ion. In some aspects, the method further includes identifying a delay between the first signal and the second signal to determine, using the identified delay, a location of the ion on the detection area.
Abstract:
Provided are a method and device for reducing the extrinsic dark count of a superconducting nanowire single photon detector (SNSPD), comprising the steps of: integrating a multi-layer film filter on the superconducting nanowire single photon detector; wherein, the multi-layer film filter is a device implemented by a multi-layer dielectric film and having a band-pass filtering function. The extrinsic dark count is the dark count triggered by optical fiber blackbody radiance and external stray light. The superconducting nanowire single photon detector comprises: a substrate having an upper surface integrated with an upper anti-reflection layer and a lower surface integrated with a lower anti-reflection layer; an optical cavity structure; a superconducting nanowire; and a reflector. The present invention is easy to operate, and only needs to integrate the multi-layer film filter on the substrate of the SNSPD to filter non-signal radiation. The method effectively reduces the extrinsic dark count while ensuring the signal radiation and the optical coupling efficiency of a device, thereby improving the detection efficiency of the device in dark count specific conditions.
Abstract:
A superconducting thermal detector (bolometer) of THz (sub-millimeter) wave radiation based on sensing the change in the amplitude or phase of a resonator circuit, consisting of a capacitor (Csh) and a superconducting temperature dependent inductor where the said inductor is thermally isolated from the heat bath (chip substrate) by micro-suspensions. The bolometer design includes a thin film inductor located on the membrane, a single or/and multi-layered thin film capacitor, and a thin film absorber of incoming radiation. The bolometer design can also include a lithographic antenna with antenna termination and/or a back reflector beneath the membrane for optimal wavelength detection by the resonance circuit. The superconducting thermal detector (bolometer) and arrays of these detectors operate in a temperature range from 1 Kelvin to 10 Kelvin.
Abstract:
The present invention discloses the low-stress niobium nitride (NbN) superconducting thin film and preparation method and application thereof. The preparation method includes the following steps: providing the metal Nb target and the Si-based substrates, fixing the Si-based substrate at room temperature, adjusting the mass flow ratio of N2/Ar to 20%-50%, the sputtering power to 50-400 W and the deposition pressure to 3.0-10.0 mTorr, NbN superconducting thin films with a stress range of-500 MPa˜500 MPa and a thickness of 70-150 nm were deposited on Si-based substrates. By synergistically controlling the mass flow rate ratio of N2/Ar, sputtering power, and deposition pressure, low stress NbN superconducting thin films can be easily and efficiently prepared. The stress range of the prepared NbN superconducting thin films meets the preparation requirements of superconducting dynamic inductance detectors, and can be mass-produced.
Abstract:
An omnidirectional measurement system for a time-varying characteristic of atmospheric vapor radiation includes an antenna and calibrator assembly, a receiver assembly, a room temperature IF assembly, and a data acquisition and system control assembly. Atmospheric vapor features a wide profile and strong radiation in a frequency band of 183 GHz, and is often seen in the characteristic measurement of atmospheric vapor in high-altitude areas. The omnidirectional measurement system combines a superconductor-insulator-superconductor (SIS) mixer with high detection sensitivity in the frequency band of 183 GHz with a structure that integrates pitch scanning, omnidirectional scanning, and automatic calibration to achieve fast and high-precision omnidirectional scanning measurement of the time-varying characteristic of atmospheric vapor radiation. The omnidirectional measurement system has a pitch adjustment-based fast omnidirectional scanning function, and can measure the time-varying characteristic of atmospheric vapor radiation with higher precision and higher temporal resolution through the SIS mixer with higher sensitivity.