Related papers: Proximity-induced superconductivity within the InA…
InSb is one of the promising candidates to realize a topological state through proximity induced superconductivity in a material with strong spin-orbit interactions. In two-dimensional systems, thin barriers are needed to allow strong…
We experimentally study electron transport across a single planar junction between the indium electrode and MnTe altermagnet candidate. We confirm standard Ohmic behavior with strictly linear current-voltage curves above the indium critical…
The two-dimensional topological insulator state in InAs/GaSb quantum wells manifests itself by topologically protected helical edge channel transport relying on an insulating bulk. This work investigates a way of suppressing bulk…
Phase winding effects in hollow semiconductor nanowires with superconducting shells have been proposed as a route to engineer topological superconducting states. We investigate GaAs/InAs core/shell nanowires with half-shells of epitaxial…
We study transport mediated by Andreev bound states formed in InSb nanowire quantum dots. Two kinds of superconducting source and drain contacts are used: epitaxial Al/InSb devices exhibit a doubling of tunneling resonances, while in…
Quantum spin Hall insulators (QSHIs) based on HgTe and three-layer InAs/GaSb quantum wells (QWs) have comparable bulk band-gaps of about 10--18~meV. The former however features a band-gap vanishing with temperature, while the gap in…
In this PhD thesis, quantum devices based on molecular-beam epitaxy grown InAs semiconductor with an in-situ grown epitaxial Al film were investigated. Novel device geometries were realized that allow for the study of bound states that…
We report the first observation of the intrinsic multiple Andreev reflections effect (IMARE) in S-n-S-...-S-arrays (S = superconductor, n = normal metal) formed by "break-junction" technique in GdO(F)FeAs superconductor (Tc = 48 - 53 K). We…
Many-body interactions can produce novel ground states in a condensed-matter system. For example, interacting electrons and holes can spontaneously form excitons, a neutral bound state, provided that the exciton binding energy exceeds the…
Sub-gap conductance at a large area junction with a rough interface of a ferromagnet and a high-T$_{C}$ superconductor is superimposed by multiple peaks which is not expected from an ideal point contact Andreev reflection process. We…
The superconducting proximity effect has been the focus of significant research efforts over many years and has recently attracted renewed interest as the basis of topologically non-trivial states in materials with a large spin orbit…
We report a systematic experimental study of mesoscopic conductance fluctuations in superconductor/normal/superconductor (SNS) devices Nb/InAs-nanowire/Nb. These fluctuations far exceed their value in the normal state and strongly depend on…
We study Andreev reflection in a ballistic one-dimensional channel coupled in parallel to a superconductor via a tunnel barrier of finite length $L$. The dependence of the low-energy Andreev reflection probability $R_A$ on $L$ reveals the…
Electrons incident from a normal metal onto a superconductor are reflected back as holes - a process called Andreev reflection. In a normal metal where the Fermi energy is much larger than a typical superconducting gap, the reflected hole…
In this work, we theoretically study transverse magnetic focusing in a two-dimensional electron gas with strong Rashba spin-orbit interaction when proximitized along its edge with a superconducting contact. The presence of superconducting…
We have fabricated a sub-micron-sized structure consisting of an InAs-based 2DEG, two narrow Nb leads and a gate, where the indirect ballistic transport between the non-oppositely superconducting contacts can be controlled by the voltage…
Indium Arsenide is a III-V semiconductor with low electron effective mass, a small band gap, strong spin-orbit coupling, and a large g-factor. These properties and its surface Fermi level pinned in the conduction band make InAs a good…
In a search for a simple proximity system of a topological insulator and a superconductor for studying the role of surface versus bulk effects by gating, we report here on a first step toward this goal, namely the choice of such a system…
We experimentally investigate Andreev bound states (ABSs) in a carbon nanotube quantum dot (QD) connected to a superconducting Nb lead (S). A weakly coupled normal metal contact acts as a tunnel probe that measures the energy dispersion of…
We use a superconducting microresonator as a cavity to sense absorption of microwaves by a superconducting quantum point contact defined by surface gates over a proximitized two-dimensional electron gas. Renormalization of the cavity…