Bart Roovers

Affiliation

Delft University of Technology

Title of work

Quasiparticle Poisoning Dynamics in Hybrid InSb-Al Nanowire Devices

Authors

B. Roovers$^1$, F. Zatelli$^1$, N. van Loo$^1$, T. van Caekenberghe$^1$, G. Wang$^1$, A. Bordin$^1$, D. van Driel$^1$, G.P. Mazur$^1$, L.P. Kouwenhoven$^1$

$^1$ QuTech and Kavli Institute of NanoScience, Delft University of Technology, 2600 GA Delft, The Netherlands

Abstract

The recent demonstration of a minimal Kitaev chain [1], hosting “poor man’s Majorana” states, has laid the groundwork for the development of prototypical parity qubits. The coherence times for this type of qubit are upper bounded by the parity lifetime of the individual Kitaev chains. Quasiparticle poisoning events will alter the total fermionic parity, causing the qubit to leak out of its computational subspace. To understand the quasiparticle poisoning (QPP) dynamics of such systems, we study the QPP rate of a quantum dot (QD) coupled to an Andreev bound state (ABS) in a hybrid InSb-Al nanowire. Utilizing an integrated charge sensor, we find a QPP rate on the order of a millisecond. We demonstrate that the QD effectively acts as a quasiparticle trap for the ABS. Additionally, we observe that applying an out-of-plane magnetic field perpendicular to the Al film can significantly affect the QPP dynamics.

[1] Dvir, Tom, et al. "Realization of a minimal Kitaev chain in coupled quantum dots." Nature 614.7948 (2023): 445-450