相关论文: High quality ferromagnetic 0 and pi Josephson tunn…
Self-shunted aluminum Josephson junctions with high-transparency barriers were fabricated using the shadow-evaporation technique and measured at low temperatures, T=25 mK. Due to high junction transparency, the IV-characteristics were found…
Establishment of phase-coherence and a non-dissipative (super)current between two weakly coupled superconductors, known as the Josephson effect, plays a foundational role in basic physics and applications to metrology, precision sensing,…
We have studied Josephson junctions with barriers prepared from the Heusler compound Cu$_2$MnAl. In the as-prepared state the Cu$_2$MnAl layers are non ferromagnetic and the critical Josephson current density $j_{c}$ decreases exponentially…
We show that the S/F/S Josephson $\varphi_0$-junction permits detection of macroscopic quantum tunneling and quantum oscillation of the magnetic moment by measuring the ac voltage across the junction. Exact expression for the tunnel…
The role of reduced dimensionality in high temperature superconductors is still under debate. Recently, ultracold atoms have emerged as an ideal model system to study such strongly correlated 2D systems. Here, we report on the realisation…
We investigate Josephson junctions with superconducting ferropnictides, both in the diffusive and ballistic limit. We focus on the proposed $s_\pm$-wave state, and find that the relative phase shift intrinsic to the $s_\pm$-wave state may…
We present the latest generation of superconductor-insulator-ferromagnet-superconductor Josephson tunnel junctions with a step-like thickness of the ferromagnetic (F) layer. The F-layer thicknesses $d_1$ and $d_2$ in both halves were varied…
Grain boundary bicrystal Josephson junctions of the electron-doped infinite-layer superconductor Sr$_{1-x}$La$_x$CuO$_2$ ($x = 0.15$) were grown by pulsed laser deposition. BaTiO$_3$-buffered $24\,^\circ$ [001]-tilt symmetric SrTiO$_3$…
High quality epitaxial NbN/MgO/NbN Josephson junctions have been realized with MgO barriers up to a thickness of d=1 nm. The junction properties coherently scale with the size of barrier, and low critical current densities down to 3…
The Josephson current in S-F-S junctions is described by taking into account different reflection (transmission) amplitudes for quasiparticles with spin up and down. We show that the 0-$\pi$ transition in the junctions can take place at…
We study the Josephson transport through ferromagnetic insulators (FIs) by taking into account its band structure explicitly. In the case of the fully polarized FIs (FPFIs), we found the formation of a pi-junction and an atomic-scale 0-pi…
The Josephson junction is a crucial element in superconducting devices, and niobium is a promising candidate for the superconducting material due to its large energy gap relative to aluminum. AlO$_x$ has long been regarded as the highest…
Tunneling defects in disordered materials form spurious two-level systems which are a major source of decoherence for micro-fabricated quantum devices. For superconducting qubits, defects in tunnel barriers of submicrometer-sized Josephson…
Conventional superconductor/insulator/superconductor (SIS) Josephson junctions, devices where two superconductors are separated by a tunnel barrier are technologically important as elements in quantum circuits, particularly with their key…
Proximity-induced superconductivity in a ferromagnet can induce Cooper pairs with a finite center-of-mass momentum. The resultant spatially modulated superconducting order parameter is able to stabilize Josephson junctions (JJs) with pi…
The concept of thermophase refers to the appearance of a phase gradient inside a superconductor originating from the presence of an applied temperature bias across it. The resulting supercurrent flow may, in suitable conditions, fully…
We fabricated small-size stacks on the surface of Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ (BSCCO-2212) single crystals with the bulk transition temperature $T_c$$\simeq$90 K, each containing a few intrinsic Josephson junctions. Below a critical…
In this paper we extend our earlier analysis of the novel Josephson effect in triplet superconductor--ferromagnet--triplet superconductor (TFT) junctions [B. Kastening \emph{et al.}, Phys. Rev. Lett. {\bf{96}}, 047009 (2006)]. In our more…
We present a quantitative study of the current-voltage characteristics (CVC) of diffusive superconductor/ insulator/ ferromagnet/ superconductor (SIFS) tunnel Josephson junctions. In order to obtain the CVC we calculate the density of…
We have developed a combined photolithography and electron-beam lithography fabrication process for sub-\mum to \mum-size Nb/Al-AlOx/Nb Josephson junctions. In order to define the junction size and protect its top electrode during anodic…