相关论文: Radio-frequency point-contact electrometer

We present the results of high-frequency mixing experiments performed upon parallel quantum point-contacts defined in the two-dimensional electron gas of an Al_{x}Ga_{1-x}As/GaAs-heterostructure. The parallel geometry, fabricated using a…

We describe a quasi-optical multifrequency ESR spectrometer operating in the 75-225 GHz range and optimized at 210 GHz for general use in condensed matter physics, chemistry and biology. The quasi-optical bridge detects the change of mm…

Rapid single shot spin readout is a key ingredient for fault tolerant quantum computing with spin qubits. An RF-SET (radio-frequency single electron transistor) is predominantly used as its the readout timescale is far shorter than the spin…

Point contact spectroscopy (PCS) is a technique which can reveal the size and symmetry of a superconducting gap ($\Delta$) and is especially useful for new materials such as the iron-based superconductors. PCS is usually employed in…

Creating a transmon qubit using semiconductor-superconductor hybrid materials not only provides electrostatic control of the qubit frequency, it also allows parts of the circuit to be electrically connected and disconnected in situ by…

We have developed a digital fast Fourier transform (FFT) spectrometer made of an analog-to-digital converter (ADC) and a field-programmable gate array (FPGA). The base instrument has independent ADC and FPGA modules, which allow us to…

We report on the realization of a few-electron double quantum dot defined in a two-dimensional electron gas by means of surface gates on top of a GaAs/AlGaAs heterostructure. Two quantum point contacts (QPCs) are placed in the vicinity of…

We studied enhanced superconductivity in point contacts (PCs) based on a type-I Weyl semimetal trigonal t-PtBi2 using both normal metal (Ag, Cu, Pt) and ferromagnetic (Fe, Co, Ni) tips by measuring the differential resistance dV/dI(V)…

We have fabricated and characterized a new type of electrometer that couples two parallel single-electron transistors (SETs) to a radio-frequency tank circuit for use as a differential RF-SET. We demonstrate operation of this device in…

We report on the fabrication and electronic transport characterisation of Schottky-gated strongly confined Si/SiGe quantum point contacts (QPC). At zero magnetic field and T=450mK the QPC conductance as a function of gate voltage shows a…

We present the results of point-contact spectroscopy measurements in polycrystalline RuSr_2GdCu_2O_8 samples previously characterized from both the structural and the electrical point of view. AC susceptibility and resistivity measurements,…

We present a scheme for high sensitivity charge detection in the integer quantum Hall regime using two point contacts in a series. The setup is an electronic analog of an optical Fabry-Perot interferometer. We show that for small…

We realize and model a Rydberg-state atom interferometer for measurement of phase and intensity of radio-frequency (RF) electromagnetic waves. A phase reference is supplied to the atoms via a modulated laser beam, enabling atomic…

We design a phase-sensitive Rydberg-atom interferometry by implementing Floquet electromagnetically induced transparency (FEIT). The FEIT mixes the sidebands of a Rydberg state induced by a MHz radio frequency (RF) field and recombines them…

We construct a low-temperature microwave waveguide interferometer for measuring high-frequency properties of two-dimensional electron gases (2DEGs). Coupled plasmon-cyclotron resonance (PCR) spectra are used to extract effective mass, bulk…

Radio-frequency (rf)- operated single-electron transistors (SETs) are high-sensitivity, fast-response electrometers, which are valuable for developing new insights into single-charge dynamics. We investigate high-frequency (up to 1 MHz)…

We have investigated radio-frequency single-electron transistor (RF-SET) operation of single-walled carbon nanotube quantum dots in the strong tunneling regime. At 4.2 K and carrier frequency 754.2 MHz, we reach a charge sensitivity of…

We have analyzed numerically the response and noise-limited charge sensitivity of a radio-frequency single-electron transistor (RF-SET) in a non-superconducting state using the orthodox theory. In particular, we have studied the performance…

We performed radiofrequency (RF) reflectometry measurements at 2.4 GHz on electrolyte-gated graphene field-effect transistors (GFETs) utilizing a tunable stub-matching circuit for impedance matching. We demonstrate that the gate voltage…

We demonstrate fast and ultrasensitive charge detection with a cavity-embedded Cooper pair transistor (cCPT) via dispersive readout of its Josephson inductance. We report a minimum charge sensitivity of $14$ $\mu e/\sqrt{\mathrm{Hz}}$ with…