Charge-noise tolerant exchange gates of singlet-triplet qubits in asymmetric double quantum dots

Abstract

In the semi-conductor double quantum dot singlet-triplet qubit architecture, the decoherence caused by the qubit's charge environment poses a serious obstacle in the way 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 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 intra-dot tunneling using magnetic fields, while the smaller dot and its larger splitting can be used in the projective readout of the qubit.

References in corpus (9)

• Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits
• Universal quantum control of two-electron spin quantum bits using dynamic nuclear polarization
• Electrometry Using Coherent Exchange Oscillations in a Singlet-Triplet-Qubit
• Universal set of quantum gates for double-dot spin qubits with fixed interdot coupling
• Noise-resistant control for a spin qubit array
• Conditional operation of a spin qubit
• Quantum gates between capacitively coupled double quantum dot two-spin qubits
• Coherent Adiabatic Spin Control in the Presence of Charge Noise Using Tailored Pulses
• Inverted Singlet-Triplet Qubit Coded on a Two-Electron Double Quantum Dot

Cited by in corpus (5)

• Validity of the single-particle description and charge noise resilience for multielectron quantum dots
• Quantum dot molecule devices with optical control of charge status and electronic control of coupling
• A robust operating point for capacitively coupled singlet-triplet qubits
• Nonmonotonic buildup of spin-singlet correlations in a double quantum dot
• Gate-based protocol simulations for quantum repeaters using quantum-dot molecules in switchable electric fields