121 citations · 516 across the 22 of their papers we have counts for
22 papers
Rashba spin-orbit coupling and artificially engineered topological superconductors
Sankar Das Sarma, Katharina Laubscher, Haining Pan +2
One of the most important physical effects in condensed matter physics is the Rashba spin-orbit coupling (RSOC), introduced in seminal works by Emmanuel Rashba. In this article, we…
Fractional chiral second-order topological insulator from a three-dimensional array of coupled wires
Viktoriia Pinchenkova, Katharina Laubscher, Jelena Klinovaja
We construct a model of a three-dimensional chiral second-order topological insulator (SOTI) from an array of weakly coupled nanowires. We show that, in a suitable parameter regime…
Singlet-only Always-on Gapless Exchange Qubits with Baseband Control
Nathan L. Foulk, Silas Hoffman, Katharina Laubscher +1
We propose a singlet-only always-on gapless exchange (SAGE) spin qubit that encodes a single qubit in the spins of four electrons while allowing universal baseband control. While c…
Detection of Majorana zero modes bound to Josephson vortices in planar superconductor-topological insulator-superconductor junctions
Katharina Laubscher, Jay D. Sau
We study signatures of Majorana zero modes (MZMs) bound to Josephson vortices in superconductor-three-dimensional topological insulator-superconductor (S-TI-S) Josephson junctions…
Quantum computation with hybrid parafermion-spin qubits
Denis V. Kurlov, Melina Luethi, Anatoliy I. Lotkov +3
We propose a universal set of single- and two-qubit quantum gates acting on a hybrid qubit formed by coupling a quantum dot spin qubit to a parafermion qubit with…
Germanium-based hybrid semiconductor-superconductor topological quantum computing platforms: Disorder effects
Katharina Laubscher, Jay D. Sau, Sankar Das Sarma
It was recently suggested that proximitized gate-defined Ge hole nanowires could serve as an alternative materials platform for the realization of topological Majorana zero modes (…
Majorana zero modes in gate-defined germanium hole nanowires
Katharina Laubscher, Jay D. Sau, Sankar Das Sarma
We theoretically study gate-defined one-dimensional channels in planar Ge hole gases as a potential platform for non-Abelian Majorana zero modes. We model the valence band holes in…
Majorana bound states in germanium Josephson junctions via phase control
Melina Luethi, Henry F. Legg, Katharina Laubscher +2
We consider superconductor-normal-superconductor-normal-superconductor (SNSNS) planar Josephson junctions in hole systems with spin-orbit interaction that is cubic in momentum (CSO…
Apparent Kondo effect in Moiré TMD bilayers: Heavy fermions or disorder?
Prathyush P. Poduval, Katharina Laubscher, Sankar Das Sarma
A recent work by Zhao et al. [1] reports the realization of a synthetic Kondo lattice in a gate-tunable Moiré TMD bilayer system. The observation of a Kondo lattice is supported by…
Parity protected superconducting diode effect in topological Josephson junctions
Henry F. Legg, Katharina Laubscher, Daniel Loss +1
In bulk superconductors or Josephson junctions formed in materials with spin-orbit interaction, the critical current can depend on the direction of current flow and applied magneti…
RKKY interaction in one-dimensional flat-band lattices
Katharina Laubscher, Clara S. Weber, Maximilian Hünenberger +4
We study the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between two classical magnetic impurities in one-dimensional lattice models with flat bands. As two representative exa…
Planar Josephson junctions in germanium: Effect of cubic spin-orbit interaction
Melina Luethi, Katharina Laubscher, Stefano Bosco +2
Planar Josephson junctions comprising semiconductors with strong spin-orbit interaction (SOI) are promising platforms to host Majorana bound states (MBSs). Previous works on MBSs i…
Fractional second-order topological insulator from a three-dimensional coupled-wires construction
Katharina Laubscher, Pim Keizer, Jelena Klinovaja
We construct a three-dimensional second-order topological insulator with gapless helical hinge states from an array of weakly tunnel-coupled Rashba nanowires. For suitably chosen i…
RKKY interaction at helical edges of topological superconductors
Katharina Laubscher, Dmitry Miserev, Vardan Kaladzhyan +2
We study spin configurations of classical magnetic impurities placed close to the edge of a two-dimensional topological superconductor both analytically and numerically. First, we…
Majorana bound states in semiconducting nanostructures
Katharina Laubscher, Jelena Klinovaja
In this Tutorial, we give a pedagogical introduction to Majorana bound states (MBSs) arising in semiconducting nanostructures. We start by briefly reviewing the well-known Kitaev c…
Fractional boundary charges with quantized slopes in interacting one- and two-dimensional systems
Katharina Laubscher, Clara S. Weber, Dante M. Kennes +4
We study fractional boundary charges (FBCs) for two classes of strongly interacting systems. First, we study strongly interacting nanowires subjected to a periodic potential with a…
Kramers pairs of Majorana corner states in a topological insulator bilayer
Katharina Laubscher, Danial Chughtai, Daniel Loss +1
We consider a system consisting of two tunnel-coupled two-dimensional topological insulators proximitized by a top and bottom superconductor with a phase difference of between…
Majorana zero modes and their bosonization
Victor Chua, Katharina Laubscher, Jelena Klinovaja +1
The simplest continuum model of a one-dimensional non-interacting superconducting fermionic symmetry-protected topological (SPT) phase is studied in great detail using analytical m…
Majorana and parafermion corner states from two coupled sheets of bilayer graphene
Katharina Laubscher, Daniel Loss, Jelena Klinovaja
We consider a setup consisting of two coupled sheets of bilayer graphene in the regime of strong spin-orbit interaction, where electrostatic confinement is used to create an array…
Fractional Topological Superconductivity and Parafermion Corner States
Katharina Laubscher, Daniel Loss, Jelena Klinovaja
We consider a system of weakly coupled Rashba nanowires in the strong spin-orbit interaction (SOI) regime. The nanowires are arranged into two tunnel-coupled layers proximitized by…
Universal quantum computation in the surface code using non-Abelian islands
Katharina Laubscher, Daniel Loss, James R. Wootton
The surface code is currently the primary proposed method for performing quantum error correction. However, despite its many advantages, it has no native method to fault-tolerantly…
Poking holes and cutting corners to achieve Clifford gates with the surface code
Benjamin J. Brown, Katharina Laubscher, Markus S. Kesselring +1
The surface code is currently the leading proposal to achieve fault-tolerant quantum computation. Among its strengths are the plethora of known ways in which fault-tolerant Cliffor…