The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Terahertz (THz) direct detectors based on superconducting niobium nitride (NbN) hot electron bolometers (HEBs) with microwave (MW) injection have been studied. Compared to the thermal biasing method, the injected MW is used here to bias the HEB to the optimum point. MW can be expected to be used as the easy read out for the detecting array. The used NbN HEB has an excellent performance as heterodyne...
Short-range wireless terahertz (THz) communication and ultrafast THz interconnects require switches and modulators. Here, we experimentally show voltage-bias superconducting (SC) niobium nitride (NbN) metamaterial to realize a switch. The obtained maximum transmission coefficient at 0.507 THz is up to 0.98 and it drops to 0.19 when the applied voltage is only increased to 0.9 V. A relative transmittance...
This paper presents a terahertz (THz) spectrometer based on high temperature superconducting Josephson junction. The YBa2Cu3O7 (YBCO) bi-crystal Josephson junctions (JJS) with log-periodic antennas are used as detectors. In the low temperature, with the signal measurement, data acquisition and human-computer interactive system, the automatic measurement system of THz spectrometer is finally accomplished...
A system to detect the terahertz (THz) pulse signals has been studied based on the superconducting NbN hot electron bolometer (HEB) detectors, which has the noise equivalent power (NEP) of 9×10−12 W/√Hz, together with a Fourier transform spectrometer (FTS). The detector has been driven by an easily adjustable microwave source to its best bias working point, and its output shown a linear relationship...
In recent years coherent terahertz (THz) radiation from stacks containing nearly 1000 Bi2Sr2CaCu2O8 (BSCCO) intrinsic Josephson junctions (IJJs) has attracted a lot of research interest. However, in most cases, reported have been frequencies well below 1 THz, or typically around 500 GHz, which obviously can be a bottleneck for many applications. In our experiments, by optimizing sample structures...
Using the Y-factor measurement method, we estimated the noise figure (NF) of the high temperature superconducting bi-crystal Josephson junction mixer. The experiment was based on small pulse tube refrigerator, working at 60 K. We tested and analysed the dependence of bias voltage and local oscillation signal power with the noise figure.
We present analytical and experimental thermal characteristics of a battery-less, fully-passive wireless backscattering microsystem for recording of neuropotentials. A major challenge for cortically implantable microsystems involves minimizing the heat dissipated by on-chip circuitry, which can lead to permanent brain damage. Therefore, knowledge of temperature changes induced by implantable microsystems...
The metal implants have been widely used for the human skeleton in dental, maxillofacial and orthopedic treatments for many years. The main function of the implant is to reinforce the fractured bone or provide a direct attachment for a prosthetic limb. The mechanical based orthopedic fixation normally uses a self-tapping implant to provide connectivity between fractured bones. In such a system, the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.