相关论文: Radio-frequency impedance measurements using a tun…
We present microwave frequency measurements of the dynamic admittance of a quantum dot tunnel coupled to a two-dimensional electron gas. The measurements are made via a high-quality 6.75 GHz on-chip resonator capacitively coupled to 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 use spin-transfer-driven ferromagnetic resonance (ST-FMR) to measure the spin-transfer torque vector T in MgO-based magnetic tunnel junctions as a function of the offset angle between the magnetic moments of the electrodes and as a…
A custom-developed magneto-mechanical resonator (MMR) for wireless pressure measurement is investigated for potential applications in process engineering. The MMR sensor utilises changes in the resonance frequency caused by pressure on a…
A precision radio-frequency (RF) transverse modulation technique based on a resonant tunnel diode oscillator (TDO) has been used to study the dynamic susceptibility in novel ring-shaped single domain Fe nanoparticles synthesized using…
The microwave cavity perturbation method is often used to determine material parameters (electric permittivity and magnetic permeability) at high frequencies and it relies on measurement of the resonator parameters. We present a method to…
This paper describes the impedance spectroscopy adapted for analysis of small electrochemical changes in fluids. To increase accuracy of measurements the differential approach with temperature stabilization of fluid samples and electronics…
A sensitive tunnel diode oscillator (TDO) operating at 4MHz is used to probe the dynamic response of La_{1-x}Sr_{x}MnO_{3} single crystals for x=0.125,0.175,0.28 and 0.33 doping. Systematics of the measured change in reactance as a function…
The wire method is a more rapid and less costly method to measure impedances of RF components compared to methods using a beam. A setup using a single displaced wire to excite and measure transverse resonant modes in accelerating structures…
A method is presented to measure the absolute value of the London penetration depth, $\lambda$, from the frequency shift of a resonator. The technique involves coating a high-$T_c$ superconductor (HTSC) with film of low - Tc material of…
The Kondo effect describes the scattering of conduction electrons by magnetic impurities, manifesting as an electronic resonance at the Fermi energy with a distinctive temperature evolution. In this letter, we present a critical evaluation…
A method for measuring the degree of spin polarization of magnetic materials based on spin-dependent resonant tunneling is proposed. The device we consider is a ballistic double-barrier resonant structure consisting of a ferromagnetic layer…
Perovskites have proven to be a promising candidate for highly-efficient solar cells, light-emitting diodes, and X-ray detectors, overcoming limitations of inorganic semiconductors. However, they are notoriously unstable. The main reason…
From studies of exotic quantum many-body phenomena to applications in spintronics and quantum information processing, topological materials are poised to revolutionize the condensed matter frontier and the landscape of modern materials…
In this paper we present several techniques for characterizing longitudinal impedances based on transient measurements of the growth rates and tune shifts of unstable coupled-bunch modes. These techniques are applicable to measurement of…
We developed a resistance measurement using radio frequency reflection to investigate the electrical transport characteristics under destructive pulsed magnetic fields above 100 T. A homemade flexible printed circuit for a sample stage…
We analyze microwave cavity perturbation methods, and show that the technique is an excellent, precision method to study the dynamic magnetic and dielectric response in the $GHz$ frequency range. Using superconducting cavities, we obtain…
Measurements monitoring the inductive coupling between oscillating radio-frequency magnetic fields and objects of interest create versatile platforms for non-destructive testing. The benefits of ultra low frequency measurements, i.e., below…
The impedance measurement technique consists in that the phase-dependent (parametric) inductance of the system is probed by the classical tank circuit via measuring the voltage. The notion of the parametric inductance for the impedance…
We report the design and operation of a versatile tunnel diode oscillator for high sensitivity (50 ppb) measurements of the magnetic susceptibility of samples over a wide temperature range (1.7-100 K) that can be used with a simple liquid…