Library
local_library Home Repository

Universal control of four singlet–triplet qubits

Journal Article (2024)
Authors

Xin Zhang (TU Delft - QuTech Advanced Research Centre, Kavli institute of nanoscience Delft, TU Delft - QCD/Vandersypen Lab)

Elizaveta Morozova (Student TU Delft, Kavli institute of nanoscience Delft)

M.F. Russ (TU Delft - QuTech Advanced Research Centre, TU Delft - QCD/Rimbach-Russ, Kavli institute of nanoscience Delft)

D. Jirovec (Kavli institute of nanoscience Delft, TU Delft - QuTech Advanced Research Centre, TU Delft - QCD/Vandersypen Lab)

Tzu Kan Hsiao (Kavli institute of nanoscience Delft, TU Delft - QCD/Vandersypen Lab, TU Delft - QuTech Advanced Research Centre)

P. Cova Fariña (TU Delft - QCD/Vandersypen Lab, TU Delft - QuTech Advanced Research Centre, Kavli institute of nanoscience Delft)

C.A. Wang (Kavli institute of nanoscience Delft, TU Delft - QuTech Advanced Research Centre, TU Delft - QCD/Veldhorst Lab)

S.D. Oosterhout (TU Delft - BUS/TNO STAFF, TU Delft - QuTech Advanced Research Centre)

Amir Sammak (TU Delft - BUS/TNO STAFF, TU Delft - QuTech Advanced Research Centre)

Giordano Scappucci (TU Delft - QCD/Scappucci Lab, TU Delft - QuTech Advanced Research Centre, Kavli institute of nanoscience Delft)

Menno Veldhorst (TU Delft - QN/Veldhorst Lab, TU Delft - QuTech Advanced Research Centre, Kavli institute of nanoscience Delft)

L.M.K. Vandersypen (TU Delft - QN/Vandersypen Lab, TU Delft - QuTech Advanced Research Centre, Kavli institute of nanoscience Delft)

Research Group
QCD/Vandersypen Lab
To reference this document use:
https://doi.org/10.1038/s41565-024-01817-9
More Info
expand_more
Publication Year
2024
Language
English
Research Group
QCD/Vandersypen Lab
Volume number
20
Pages (from-to)
209-215
DOI:
https://doi.org/10.1038/s41565-024-01817-9
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

The coherent control of interacting spins in semiconductor quantum dots is of strong interest for quantum information processing and for studying quantum magnetism from the bottom up. Here we present a 2 × 4 germanium quantum dot array with full and controllable interactions between nearest-neighbour spins. As a demonstration of the level of control, we define four singlet–triplet qubits in this system and show two-axis single-qubit control of each qubit and SWAP-style two-qubit gates between all neighbouring qubit pairs, yielding average single-qubit gate fidelities of 99.49(8)–99.84(1)% and Bell state fidelities of 73(1)–90(1)%. Combining these operations, we experimentally implement a circuit designed to generate and distribute entanglement across the array. A remote Bell state with a fidelity of 75(2)% and concurrence of 22(4)% is achieved. These results highlight the potential of singlet–triplet qubits as a competing platform for quantum computing and indicate that scaling up the control of quantum dot spins in extended bilinear arrays can be feasible.