相关论文: Circuit with small-capacitance high-quality Nb Jos…
An ion beam based dry etching method has been developed for progressive reduction of dimensions of prefabricated nanostructures. The method has been successfully applied to aluminum nanowires and aluminum single electron transistors (SET).…
Bottom-up synthesized GNRs and GNR heterostructures have promising electronic properties for high performance field effect transistors (FETs) and ultra-low power devices such as tunnelling FETs. However, the short length and wide band gap…
A new method to fabricate non-superconducting mesoscopic tunnel junctions by oxidation of Ti is presented. The fabrication process uses conventional electron beam lithography and shadow deposition through an organic resist mask.…
Superconductor qubits typically use aluminum-aluminum oxide tunnel junctions to provide the non-linear inductance. Junctions with semiconductor barriers make it possible to vary the superconductor material and explore beyond aluminum. We…
We have fabricated and characterized asymmetric gap-engineered junctions and transmon devices. To create Josephson junctions with asymmetric gaps, Ti was used to proximitize and lower the superconducting gap of the Al counter-electrode. DC…
The dependence of the critical current density j_c on the ferromagnetic interlayer thickness d_F was determined for Nb/Al_2O_3/Cu/Ni/Nb Josephson tunnel junctions with ferromagnetic \Ni interlayer from very thin film thicknesses (\sim 1 nm)…
A superconductor-normal metal-superconductor mesoscopic Josephson junction has been realized in which the critical current is tuned through normal current injection using a symmetric electron cooler directly connected to the weak link. Both…
Thermoelectric effects in metals are typically small due to the nearly-perfect particle-hole (PH) symmetry around their Fermi surface [1, 2]. Despite being initially considered paradoxical [3], thermophase effects [4-8] and linear…
Superconducting junctions with a ferromagnet as the weak link, where triplet correlations can transport supercurrents over a substantial distance, have been of long-standing interest. In this work, we study the triplet transport in planar…
Qubits on solid state devices could potentially provide the rapid control necessary for developing scalable quantum information processors. Materials innovation and design breakthroughs have increased functionality and coherence of qubits…
Hybrid Superconductor-Semiconductor (S-Sm) materials systems are promising candidates for quantum computing applications. Their integration into superconducting electronics has enabled on-demand voltage tunability at millikelvin…
In thin superconducting wires, phase-slip by thermal activation near the critical temperature is a well-known effect. It has recently become clear that phase-slip by quantum tunnelling through the energy barrier can also have a significant…
Polarization engineered interband tunnel junctions (TJs) are integrated in nanowire ultraviolet (UV) light emitting diodes (LEDs). A ~6V reduction in turn-on voltage is achieved by the integration of tunnel junction at the base of…
Single atom junctions between superconducting niobium leads are produced using the Mechanically Controllable Break Junction technique. The current-voltage characteristics of these junctions are analysed using an exact formulation for a…
Measurements of conductance spectra in a superconductor - topological insulator - normal metal thin film junctions of NbN-$\rm Bi_2Se_3$-Au are reported. Junctions with ex-situ and in-situ prepared $\rm NbN-Bi_2Se_3$ interfaces were…
The operation of resistively-coupled single-electron transistor (R-SET) is studied quantitatively. Due to the Nyquist noise of the coupling resistance, degradation of the R-SET performance is considerable at temperatures $T$ as small as…
Graphene-based electromechanical resonators have attracted much interest recently because of the outstanding mechanical and electrical properties of graphene and their various applications. However, the coupling between mechanical motion…
We report on high quality local tunnel spectroscopy measurements in superconductors using in-situ fabricated superconducting tips as counterelectrode. The experiments were made at very low temperatures using a dilution refrigerator and a…
The controlled tunability of superconductivity in low-dimensional materials may enable new quantum devices. Particularly in triplet or topological superconductors, tunneling devices such as Josephson junctions etc. can demonstrate exotic…
Currently, superconductor digital integrated circuits fabricated at HYPRES, Inc. can operate at clock frequencies of ~ 40 GHz. The circuits present multilayered structures containing tens of thousands of Nb/Al/AlOx/Nb Josephson junctions…