We propose a quantum-circuit refrigerator (QCR) based on photon-assisted quasiparticle tunneling through single normal-metal–insulator–superconductor (NIS) junction. In contrast to previous studies with multiple junctions and an additional charge island for the QCR, we directly connect NIS junction inductively shunted electrode of superconducting microwave resonator making device immune low-fre...

Bicrystal grain boundary (GB) Josephson junctions and rf-SQUID’s were made of 200 nm thick PLD YBCO films on bi-crystal SrTiO3 substrates. The junction characteristics were studied to investigate optimal parameters in the rf-SQUID layout designs and the limits imposed by the technology. The of 3 to 8 m wide test junctions scaled with the junction widths, showing clear linear RSJ-like – characte...

We have investigated the static, charge-trapping properties of a hybrid superconductor–normal metal electron turnstile embedded in a highohmic environment. The device includes a local Cr resistor on one side of the turnstile, and a superconducting trapping island on the other side. The electron hold times, τ ∼ 2–20 s, in our two-junction circuit are comparable with those of typical multi-juncti...

We propose and analyze theoretically an experimental setup for detecting the elusive Majorana particle in semiconductor-superconductor heterostructures. The experimental system consists of one-dimensional semiconductor wire with strong spin-orbit Rashba interaction embedded into a superconducting quantum interference device. We show that the energy spectra of the Andreev bound states at the jun...

We present a theory and measurements of noise mechanisms in superconducting tunnel-junction detectors used as single-photon spectrometers. These mechanisms result from incomplete cooling of the excited quasiparticles in the tunnel-junction electrode. Due to the incomplete cooling, only a fraction of the initially created charge is collected by tunneling. Additional effects include reduced dynam...

Carbon nanotube Josephson junctions in the open quantum dot limit are fabricated using Pd/Al bilayer electrodes, and exhibit gate-controlled superconducting switching currents. Shapiro voltage steps can be observed under radio frequency current excitations, with a damping of the phase dynamics that strongly depends on the gate voltage. These measurements are described by a standard resistively ...

The electrical noise of mesoscopic devices can be strongly influenced by the quantum motion of electrons. To probe this effect, we have measured the current fluctuations at high frequency (5 to 90 gigahertz) using a superconductor-insulator-superconductor tunnel junction as an on-chip spectrum analyzer. By coupling this frequency-resolved noise detector to a quantum device, we can measure the h...

A superconducting quantum interference device (SQUID) comprising 0- and $\pi$-Josephson junctions (JJs), called $\pi$-SQUID, is studied by the resistively shunted junction model. The $\pi$-SQUID shows half-integer Shapiro-steps (SS) under microwave irradiation at voltage $V$ = $(\hbar/2e)\Omega (n/2)$, with angular frequency $\Omega$ $n$/2 in addition to integer $n$. We show that can be a $\pi$...

In this paper, photodetection properties of a Graphene-based device at the third telecommunication window have been reported. The structure of the device is a Graphene-silicon Schottky junction which has been simulated in the form of an infrared photodetector. Graphene has specific electrical and optical properties which makes this material a good candidate for optoelectronic applications. Phot...