The parallel plate resonator method has been used for measuring high quality YBa2Cu3O7−x (YBCO) thin films, which have low temperature residual losses comparable to those previously obtained in single crystals. The surface resistance and the real part of the conductivity show a non-monotonic behaviour with a broad peak around 45 K. The penetration depth and the real part of the conductivity var...

We have used the Low-Temperature Laser Scanning Microscope (LTLSM) technique for a spatially resolved investigation of the microwave transport properties, nonlinearities, and material inhomogeneities in an operating coplanar waveguide YBa2Cu3O7−δ (YBCO) microwave resonator on a LaAlO3 (LAO) substrate. The influence of twin-domain blocks, in-plane rotated grains, and micro-cracks in the YBCO fil...

We examine the application of Josephson radiation emitters to spectral calibration of singlephoton-resolving detectors. Josephson junctions were patterned in a YBCO film on a bi-crystal sapphire substrate and were voltage controlled to generate radiation in the frequency range of 0.051 THz. The detector used in this work consisted of a gate-defined quantum dot photon-to-charge transducer couple...

Inelastic Neutron Scattering (INS) data in La2-xSrxCuO4 (LSCO), YBa2Cu3O6+x (YBCO) and Bi2Sr2CaCu2O8+x (Bi2212) are discussed. In the literature, the INS spectra remain far from being comprehensively understood. We show that local (Q-integrated) susceptibility data and the energy dependence of the spin susceptibility at antiferromagnetic vector, QAF = (π,π), can be interpreted by using the phas...

We report on the fabrication and characterization of nanopatterned superconducting quantum interference devices (SQUIDs) based grain boundary Josephson junctions in epitaxially grown multilayer YBa2Cu3O7 (YBCO)/SiTrO3 (STO) thin films. Nanopatterning is performed by Ga+ focused ion beam milling. The evolution electric transport noise properties YBCO nanoSQUIDs over a time span more than one yea...

The planar oxygen isotope effect coefficient measured as a function of hole doping in the Prand La-doped YBa2Cu3O7 (YBCO) and the Ni-doped La1.85Sr0.15CuO4 (LSCO) superconductors quantitatively and qualitatively follows the form originally proposed by Kresin andWolf [Phys. Rev. B 49, 3652 (1994)], which was derived for polarons perpendicular to the superconducting planes. Interestingly, the inv...

Civale et al. have recently measured the irreversibility line of YBa2Cu307 „(YBCO)films in the magnetic field-temperature plane, B;„(T),as a function of film thickness. We are able to reproduce the observed shift of B;„(T) to lower temperatures as the film thickness is reduced within a model of Aux-linelattice melting without pinning. While pinning must be important, this suggests B;„(T) is at ...

This letter describes the scaling behavior and Josephson properties of improved YBCO/PBCO/ YBCO edge-type junctions. The critical current, normal-state resistance, and I& product scale with barrier thickness and junction area. The coherence length of the PBCO barrier is estimated to be between 5 and 8 nm. As unambiguous evidence of the Josephson behavior, the microwave response as a function of...

We report on the effect of oxygen disorder in the CuO chains on the superconducting properties of oxygen depleted YBa2Cu3Ox(YBCO). While moderate disorder, induced thermally, depresses the critical temperature as a result of a reduced carrier concentration, strong oxygen disorder and chain fragmentation induced by low energy ~80 keV! He irradiation suppresses the critical temperature beyond the...