相关论文: Coherent excited states in superconductors due to …
Processes that lead to the critical-current suppression and change of impedance of a superconductor under the application of an external voltage is an active area of research, especially due to various possible technological applications.…
Spatial fluctuations of the effective pairing interaction between electrons in a superconductor induce variations of the order parameter which in turn lead to significant changes in the density of states. In addition to an overall reduction…
We have measured the effect of microwave irradiation on the dc current-voltage characteristics of superconducting atomic contacts. The interaction of the external field with the ac supercurrents leads to replicas of the supercurrent peak,…
Quantum states inevitably decay with time into a probabilistic mixture of classical states, due to their interaction with the environment and measurement instrumentation. We present the first measurement of the decoherence dynamics of…
We present theoretical results for superradiance, i.e. the collective coherent decay of a radiating system, in semiconductor structures. An optically active region can become superradiant if a strong magnetic field is applied. Pumping of…
The magnetic field dependence of the electronic specific heat C(H) in the s-wave superconductor NbSe_2 shows curvature at low fields, resembling the near H^1/2 term in C(H) which has been reported in high-T_c superconductors and attributed…
Metals interacting via short-range antiferromagnetic fluctuations are unstable to sign-changing superconductivity at low temperatures. For the cuprates, this leading instability leads to the well known $d-$wave superconducting state.…
We characterize the behaviour of split ring resonators made up of high-transition temperature YBCO superconductor using terahertz time domain spectroscopy. The superconductor metamaterial shows sharp change in the transmission spectrum at…
Superconducting resonators, used in astronomy and quantum computation, couple strongly to microscopic two-level defects. We monitor the microwave response of superconducting resonators and observe fluctuations in dissipation and resonance…
Electronic Raman scattering from high- and low-energy excitations was studied as a function of temperature, extent of hole doping, and energy of the incident photons in Bi_2Sr_2CaCu_2O_{8 \pm \delta} superconductors. For underdoped…
It is shown that currents in thin-film superconducting rings irradiated by coherent microwave fields, can discretely decay with photons emission. These quantized jumps of the supercurrent correspond to destruction one or several magnetic…
We have spectroscopically measured the energy level separation of a superconducting charge qubit coupled non-resonantly to a single mode of the electromagnetic field of a superconducting on-chip resonator. The strong coupling leads to large…
The density of states of the disordered s-wave superconductor is calculated perturbatively. The effect of Coulomb interaction on diffusively moving electrons in the normal state has been known before, but in the superconducting state both…
We fabricated superconducting coplanar waveguide resonator with leads for dc bias, which enables the ac conductivity measurement under dc bias. The current and the magnetic field dependences of resonance properties were measured, and…
We discuss a new mechanism of microwave absorption in s- and d-wave superconductors, which arises in the presence of a dc supercurrent in the system. It produces a contribution to the ac conductivity that is proportional to the inelastic…
We report on transient effects in the microwave second-order response of different type of superconductors in the mixed state. The samples have contemporarily been exposed to a dc magnetic field, varying with a constant rate of 60 Oe/s, and…
We show that transport through a superconducting quantum point contact biased at subgap voltages is strongly affected by a microwave field. The subgap current is increased by several orders of magnitude. Quantum interference among resonant…
Strongly disordered superconductors (SDSCs) are widely used in qubits, microwave resonators, photon detectors, and other superconducting quantum devices. In SDSC-based devices, coherence times are limited by low-temperature microwave…
We address, using concepts of the microscopic theory of superconductivity, parametric amplifiers and kinetic inductance detectors focusing on the interaction of microwave radiation with the superconducting condensate. This interaction was…
Microwave circuit electrodynamics of disordered superconductors is a very active research topic spawning a wide range of experiments and applications. For compact superconducting circuit elements, the transition to an insulating state poses…