Superconducting qubits are solid state electrical circuits fabricated using techniques borrowed from conventional integrated circuits. They are based on the Josephson tunnel junction, the only non-dissipative, strongly non-linear circuit element available at low temperature. In contrast to microscopic entities such as spins or atoms, they tend to be well coupled to other circuits, which make th...

We investigate the ultrastrong tunable coupler for coupling of superconducting resonators. The obtained constant exceeds 1 GHz, and wide-range tunability is achieved both antiferromagnetics ferromagnetics from $\ensuremath{-}1086$ to 604 MHz. composed a rf quantum interference device (SQUID) dc SQUID as junctions, which connect resonators via shared aluminum thin-film meander lines enabling suc...

In this work, we study a series of tunable flux qubits inductively coupled to coplanar waveguide resonator fabricated on sapphire substrate. Each qubit includes an asymmetric superconducting quantum interference device which is controlled by the application external magnetic field and acts as Josephson junction. The tunability typically $\pm 3.5$ GHz around their central gap frequency. measured...

We study the microscopic structure of the Josephson current in a single-mode tunnel junction with a wide quasiclassical tunnel barrier. In such a junction each Andreev bound state carries a current of magnitude proportional to the amplitude of the normal electron transmission through the junction. Tremendous enhancement of the bound state current is caused by the resonance coupling of supercond...

Supercurrent flow between two superconductors with different order parameters, a phenomenon known as the Josephson effect, can be achieved by inserting a non-superconducting material between two superconductors to decouple their wavefunctions. These Josephson junctions have been employed in fields ranging from digital to quantum electronics, yet their functionality is limited by the interface q...

Experiments with small capacitance Josephson junction arrays are described that demonstrate the quantum behavior of the phase of the superconducting condensate. This quantum behavior is based on the complementarity of phase and number for a condensate state of many bosons. A key factor to observation of this quantum behavior is the coupling of the superconducting condensate state to dissipation...

In spite of extended efforts, detecting thermoelectric effects in superconductors has proven to be a challenging task, due to the inherent superconducting particle-hole symmetry. Here we present a theoretical study of an experimentally attainable Superconductor - Quantum Dot - Superconductor (SC-QD-SC) Josephson Junction. Using Keldysh Green's functions we derive the exact thermo-phase and ther...

Superconducting qubits are solid state electrical circuits fabricated using tech5 niques borrowed from conventional integrated circuits. They are based on the 6 Josephson tunnel junction, the only non-dissipative, strongly non-linear circuit ele7 ment available at low temperature. In contrast to microscopic entities such as 8 spins or atoms, they tend to be well coupled to other circuits, which...