Related papers: Multiple Andreev reflection and critical current i…
We report on the observation of gate-tunable proximity-induced superconductivity and multiple Andreev reflections (MAR) in a bulk-insulating BiSbTeSe$_2$ topological insulator nanoribbon (TINR) Josephson junction (JJ) with superconducting…
The Josephson effect is a fundamental quantum phenomenon consisting in the appearance of a dissipationless supercurrent in a weak link between two superconducting (S) electrodes. While the mechanism leading to the Josephson effect is quite…
Epitaxially grown, high quality semiconductor InSb nanowires are emerging material systems for the development of high performance nanoelectronics and quantum information processing and communication devices, and for the studies of new…
Superconductors with an odd number of bands crossing the Fermi energy have topologically protected Andreev states at interfaces, including Majorana states in one dimensional geometries. Superconductivity, a low number of 1D channels, large…
Superconducting proximity junctions made of topological insulator (TI) nanoribbons (NRs) provide a useful platform for studying topological superconductivity. We report on the fabrication and measurement of Josephson junctions (JJs) using…
We theoretically study coherent multiple Andreev reflections in a biased three-terminal Josephson junction. We demonstrate that the direct current flowing through the junction consists of supercurrent components when the bias voltages are…
We show that Josephson junctions made of multiband semiconductors with strong spin-orbit coupling carry a critical supercurrent $I_c$ that contains information about the non-trivial topology of the system. In particular, we find that the…
A semiconducting nanowire with strong Rashba spin-orbit coupling and coupled to a superconductor can be tuned by an external Zeeman field into a topological phase with Majorana zero modes. Here we theoretically investigate how this exotic…
A theory of coherent multiple Andreev reflections (MAR) is developed for superconductor-normal metal-superconductor (SNS) interferometers. We consider a Y-shape normal electron beam splitter connecting two superconducting reservoirs, where…
We study the stationary Josephson current in a junction between a topological and an ordinary (topologically trivial) superconductor. Such an S-TS junction hosts a Majorana zero mode that significantly influences the current-phase relation.…
We investigate transport though normal-superconductor nanowire junctions in the presence of spin-orbit coupling and magnetic field. As the Zeeman field crosses the critical bulk value B_c of the topological transition, a Majorana bound…
We have examined the electrical behavior of Josephson junctions formed by a scanning tunneling microscope (STM) with a Nb sample and a Nb tip, with normal-state resistances Rn varying between 1 kOhm and 10 MOhm. Current-voltage…
We show theoretically that in the generic finite chemical potential situation, the clean superconducting spin-orbit-coupled nanowire has two distinct nontopological regimes as a function of Zeeman splitting (below the topological quantum…
Majorana bound states in topological Josephson junctions induce a 4? period current-phase relation. Direct detection of the 4? periodicity is complicated by the quasiparticle poisoning. We reveal that Majorana bound states are also signaled…
We calculate the differential conductance at a probe inserted in the weak link of a topological Josephson junction, consisting of a semiconducting nanowire deposited on top of two separated superconductors. Our aim is to understand how the…
Andreev reflection is investigated in layered anisotropic normal metal / superconductor (N/S) systems in the case of an energy gap \Delta in S not negligible with respect to the Fermi energy E_F, as it probably occurs with high critical…
Particle transport across Josephson junctions is commonly described using a simplifying approximation (often called the Andreev approximation), which assumes that excitations are fixed at the Fermi momentum and only Andreev reflections,…
We investigate the Majorana physics and its effect on the electron transport in the non-topological superconductor(NS)-topological superconductor(TS) double junctions of a ring geometry. We find that, depending on the ratio between the…
In this work we show that Rashba-based topological superconductor nanowires, where the spin-orbit coupling may change its sign, support three topological phases protected by chiral symmetry. When a superconducting phase gradient is applied…
Non-linear charge transport in SIS Josephson junctions has a unique signature in the shuttled charge quantum between the two superconductors. In the zero-bias limit Cooper pairs, each with twice the electron charge, carry the Josephson…