Universal quantum control of two-electron spin quantum bits using dynamic nuclear polarization

2009/10/11 by Sandra Foletti, Hendrik Bluhm, D. Mahalu +4 · 12 citations
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Electron #Flux qubit #Magnetic properties of thin films #Open quantum system #Physics #Quantum #Quantum and electron transport phenomena #Quantum computer #Quantum decoherence #Quantum error correction #Quantum gate #Quantum mechanics #Quantum technology #Qubit #cond-mat.mes-hall #quant-ph

paper · pdf · doi:10.1038/nphys1424

published as Nature Physics 5, 903-908 (2009) · 11 pages, 4 figures. Supplementary Material included as ancillary file

openalex publication_date 2009/10/11 · arxiv created 2010/09/27 · arxiv updated 2010/09/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

One fundamental requirement for quantum computation is to perform universal manipulations of quantum bits at rates much faster than the qubit's rate of decoherence. Recently, fast gate operations have been demonstrated in logical spin qubits composed of two electron spins where the rapid exchange of the two electrons permits electrically controllable rotations around one axis of the qubit. However, universal control of the qubit requires arbitrary rotations around at least two axes. Here we show that by subjecting each electron spin to a magnetic field of different magnitude we achieve full quantum control of the two-electron logical spin qubit with nanosecond operation times. Using a single device, a magnetic field gradient of several hundred milliTesla is generated and sustained using dynamic nuclear polarization of the underlying Ga and As nuclei. Universal control of the two-electron qubit is then demonstrated using quantum state tomography. The presented technique provides the basis for single and potentially multiple qubit operations with gate times that approach the threshold required for quantum error correction.

Citations

• Dynamics of Quantum Dot Nuclear Spin Polarization Controlled by a Single Electron
• Universal Quantum Computation with Spin-1/2Pairs and Heisenberg Exchange
• Exponential decay in a spin bath
• Exchange-controlled single-electron-spin rotations in quantum dots
• Exchange Control of Nuclear Spin Diffusion in a Double Quantum Dot
• Coherent Manipulation of Coupled Electron Spins in Semiconductor Quantum Dots
• Coupling superconducting qubits via a cavity bus
• Control and Detection of Singlet-Triplet Mixing in a Random Nuclear Field
• Ultrafast optical rotations of electron spins in quantum dots

Cited by

• Microwave quantum optics as a direct probe of the Overhauser field in a quantum dot circuit quantum electrodynamics device
• Designing a practical high-fidelity long-time quantum memory
• Magnetic-Gradient-Free Two-Axis Control of a Valley Spin Qubit in SixGe1−x
• Spin-valley blockade in carbon nanotube double quantum dots
• Preparation of nonequilibrium nuclear spin states in double quantum dots
• Robust energy-selective tunneling readout of singlet-triplet qubits under large magnetic field gradient
• Noise-protected gate for six-electron double-dot qubit
• Charge Dynamics and Spin Blockade in a Hybrid Double Quantum Dot in Silicon
• Robust quantum gates for singlet-triplet spin qubits using composite pulses
• Randomized Benchmarking of Barrier versus Tilt Control of a Singlet-Triplet Qubit
• Temperature-dependent dynamical nuclear polarization bistabilities in double quantum dots in the spin-blockade regime
• Single-Shot Measurement of Triplet-Singlet Relaxation in aSi/SiGeDouble Quantum Dot