Electrostatical formation of the Majorana quasiparticles in the quantum dot--nanoring structure

Disorder-generated non-Abelions

Two classes of topological superconductors and Majorana modes in condensed matter systems are known to date: one, in which impurity disorder strongly suppresses topological superconducting gap and is detrimental to Majorana modes, and the other, where Majorana fermions are protected by disorder-robust superconductor gap. In this work we predict a third class of topological superconductivity and Majorana modes, in which they appear exclusively in the presence of impurity disorder. Observation and control of Majorana fermions and other non-Abelions often requires a symmetry leading to a gap in a…

最小 Kitaev 链中 Poor Man's Majoranas 的自旋交换诱导溢出

Spin-Exchange Induced Spillover on Poor Man's Majoranas in Minimal Kitaev Chains

本文提出在最小 Kitaev 链中，当 Poor Man's Majoranas 的量子点与量子自旋发生交换耦合时会产生溢出，揭示精细结构分裂与非局域零模的形成依赖于自旋统计，为量子计算器件提供了新见解。

Coherent manipulation of an Andreev spin qubit

Two promising architectures for solid-state quantum information processing are electron spins in semiconductor quantum dots and the collective electromagnetic modes of superconducting circuits. In some aspects, these two platforms are dual to one another: superconducting qubits are more easily coupled but are relatively large among quantum devices $(\sim\mathrm{mm})$, while electrostatically-confined electron spins are spatially compact ($\sim \mathrm{μm}$) but more complex to link. Here we combine beneficial aspects of both platforms in the Andreev spin qubit: the spin degree of freedom of an…

Evidence of Andreev blockade in a double quantum dot coupled to a superconductor

We design and investigate an experimental system capable of entering an electron transport blockade regime in which a spin-triplet localized in the path of current is forbidden from entering a spin-singlet superconductor. To stabilize the triplet a double quantum dot is created electrostatically near a superconducting lead in an InAs nanowire. The dots are filled stochastically with electrons of either spin. The superconducting lead is a molecular beam epitaxy grown Al shell. The shell is etched away over a wire segment to make room for the double dot and the normal metal gold lead. The quantu…