TY  - JOUR
AU  - Hiltunen, Tuukka
AU  - Bluhm, Hendrik
AU  - Mehl, Sebastian
AU  - Harju, Ari
TI  - Charge-noise tolerant exchange gates of singlet-triplet qubits in asymmetric double quantum dots
JO  - Physical review / B
VL  - 91
IS  - 7
SN  - 1098-0121
CY  - College Park, Md.
PB  - APS
M1  - FZJ-2015-01362
SP  - 075301
PY  - 2015
AB  - In the semiconductor double quantum dot singlet-triplet qubit architecture, the decoherence caused by the qubit's charge environment poses a serious obstacle towards large scale quantum computing. The effects of the charge decoherence can be mitigated by operating the qubit in the so-called sweet spot regions where it is insensitive to electrical noise. In this paper, we propose singlet-triplet qubits based on two quantum dots of different sizes. Such asymmetric double quantum dot systems allow the implementation of exchange gates with controllable exchange splitting J operated in the doubly occupied charge region of the larger dot, where the qubit has high resilience to charge noise. In the larger dot, J can be quenched to a value smaller than the intradot tunneling using magnetic fields, while the smaller dot and its larger splitting can be used in the projective readout of the qubit.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000348873800002
DO  - DOI:10.1103/PhysRevB.91.075301
UR  - https://juser.fz-juelich.de/record/187784
ER  -