TY  - JOUR
AU  - Mehl, Sebastian
AU  - Bluhm, Hendrik
AU  - DiVincenzo, David
TI  - Two-qubit couplings of singlet-triplet qubits mediated by one quantum state
JO  - Physical review / B
VL  - 90
SN  - 0163-1829
CY  - College Park, Md.
PB  - APS
M1  - FZJ-2014-03749
SP  - 045404
PY  - 2014
AB  - We describe high-fidelity entangling gates between singlet-triplet qubits (STQs) which are coupled via onequantum state (QS). The QS can be provided by a quantum dot itself or by another confined system. Theorbital energies of the QS are tunable using an electric gate close to the QS, which changes the interactionsbetween the STQs independent of their single-qubit parameters. Short gating sequences exist for controlled NOT(CNOT) operations. We show that realistic quantum dot setups permit excellent entangling operations with gateinfidelities below 10−3, which is lower than the quantum error correction threshold of the surface code. Weconsider limitations from fabrication errors, hyperfine interactions, spin-orbit interactions, and charge noise inGaAs and Si heterostructures.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000338738600014
DO  - DOI:10.1103/PhysRevB.90.045404
UR  - https://juser.fz-juelich.de/record/154402
ER  -