相关论文: Surface resistance measurements of HTS thin films …
The nonlinear surface resistance Rs of the YBa2Cu3O7-x superconducting thin films on the MgO substrates was researched in the Hakki-Coleman dielectric resonator at the microwave signal powers from -18 dBm to +30 dBm at the ultra high…
Using the dielectric resonator method, we have investigated nonlinearities in the surface impedance Zs = Rs + jXs of YBa2Cu3O7 thin films at 10 GHz as function of the incident microwave power level and temperature. The use of a rutile…
We describe quantitative imaging of the sheet resistance of metallic thin films by monitoring frequency shift and quality factor in a resonant scanning near-field microwave microscope. This technique allows fast acquisition of images at…
We propose a modified two-tone method that could be used for sensitive measurements of the intrinsic microwave surface impedance (Zs) of thin superconductor films and the tand of a low-loss dielectric. An open-gap resonator scheme is used…
We report development and measurement of a micro-fabricated compact high-temperature superconducting (HTS) metamaterial atom operating at a frequency as low as $\sim$ 53MHz. The device is a planar spiral resonator patterned out of a…
We have carried out non-linear microwave (8 GHz) surface impedance measurements of three YBaCuO thin films in dc magnetic fields $H_{dc}$ (parallel to c axis) up to 12 mT using a coplanar resonator technique. In zero dc field the three…
Lithium niobate (LNO) is a well established material for surface acoustic wave (SAW) devices including resonators, delay lines and filters. Recently, multi-layer substrates based on LNO thin films have become commercially available. Here,…
An apparatus was developed to obtain, for the first time, 2D maps of the surface resistance of the inner surface of an operating superconducting radio-frequency niobium cavity by a low-temperature laser scanning microscopy technique. This…
The work describes the capabilities of Laser Scanning Microscopy (LSM) as a spatially resolved method of testing high_Tc materials and devices. The earlier results obtained by the authors are briefly reviewed. Some novel applications of the…
This letter presents a numerical investigation of acoustic modes propagating in an LiNbO$_3$/sapphire substrate under a periodic Al grating, demonstrating the occurrence of longitudinal leaky SAWs (LLSAWs) with a unique combination of very…
A high Q-factor microwave resonator in a high magnetic field could be of great use in a wide range of fields, from accelerator design to axion dark matter search. The natural choice of material for the superconducting cavity to be placed in…
Two high-quality Y-Ba-Cu-O thin films on MgO substrates have been investigated using the coplanar resonator technique at 8 and 16 GHz. Both films exhibit an anomalous decrease in their surface impedance, Zs as a function of microwave field,…
We present measurements of the field induced changes in the 47 GHz complex resistivity, $\Delta \tilde \rho(H,T)$, in Tl$_{2}$Ba$_{2}$CaCu$_{2}$O$_{8+x}$ (TBCCO) thin films with $T_{c}\simeq$ 105 K, prepared on CeO$_{2}$ buffered sapphire…
We present measurements of the magnetic field dependent microwave surface resistance in laser-ablated YBa$_2$Cu$_3$O$_{7-\delta}$ films on SrTiO$_3$ substrates. BaZrO$_3$ crystallites were included in the films using composite targets…
We use a frequency-dependent electro-optic technique to measure the hole mobility in small molecule organic semiconductors, such as 6,13 bis(triisopropylsilylethynyl)-pentacene. Measurements are made on semiconductor films in bottom gate,…
We present a method to measure the absolute surface resistance of conductive samples at a set of GHz frequencies with superconducting lead stripline resonators at temperatures 1- 6K. The stripline structure can easily be applied for bulk…
High-temperature superconducting YBa2Cu3O7-d (YBCO) thin-film detectors with improved responsivities were developed for fast time-domain measurements in the THz frequency range. YBCO thin films of 30 nm thickness were patterned to micro-…
A laser scanning microscope with a thermal spot size of about 4 $\mu$m is used to measure a quantity proportional to the rf current density in an operating superconducting co-planar waveguide microwave resonator. The twinning of the…
We have developed a low temperature, high-resolution microwave surface impedance probe that is able to operate in high static magnetic fields. Surface impedance is measured by cavity perturbation of dielectric resonators, with sufficient…
We studied surface and electronic structures of barium stannate (BaSnO$_3$) thin-film by low energy electron diffraction (LEED), and angle-resolved photoemission spectroscopy (ARPES) techniques.…