Two-Qubit Couplings of Singlet-Triplet Qubits Mediated by One Quantum State

Abstract

We describe high-fidelity entangling gates between singlet-triplet qubits (STQs) which are coupled via one quantum state (QS). The QS can be provided by a quantum dot itself or by another confined system. The orbital energies of the QS are tunable using an electric gate close to the QS, which changes the interactions between the STQs independent of their single-qubit parameters. Short gating sequences exist for the controlled NOT (CNOT) operations. We show that realistic quantum dot setups permit excellent entangling operations with gate infidelities below $10^{-3}$, which is lower than the quantum error correction threshold of the surface code. We consider limitations from fabrication errors, hyperfine interactions, spin-orbit interactions, and charge noise in GaAs and Si heterostructures.

arXiv comment12 pages, 6 figures

References in corpus (39)

• Quantum Computation with Quantum Dots
• Surface codes: Towards practical large-scale quantum computation
• Coupled quantum dots as quantum gates
• Silicon Quantum Electronics
• Coherent control of a single electron spin with electric fields
• Universal Quantum Computation with the Exchange Interaction
• Electrically driven single electron spin resonance in a slanting Zeeman field
• Schrieffer-Wolff transformation for quantum many-body systems
• Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits
• Triplet-Singlet Spin Relaxation via Nuclei in a Double Quantum Dot
• A geometric theory of non-local two-qubit operations
• Universal quantum control of two-electron spin quantum bits using dynamic nuclear polarization
• Universal quantum computation with spin-1/2 pairs and Heisenberg exchange
• Quantum Coherence in a One-Electron Semiconductor Charge Qubit
• Nonlocal properties of two-qubit gates and mixed states and optimization of quantum computations
• Relaxation, dephasing, and quantum control of electron spins in double quantum dots
• Electrometry Using Coherent Exchange Oscillations in a Singlet-Triplet-Qubit
• Coherent single electron spin control in a slanting Zeeman field
• Enhancing the Coherence of a Spin Qubit by Operating it as a Feedback Loop That Controls its Nuclear Spin Bath
• Self-Consistent Measurement and State Tomography of an Exchange-Only Spin Qubit
• The Resonant Exchange Qubit
• Ultrafast optical control of entanglement between two quantum dot spins
• Two-qubit Gate of Combined Single Spin Rotation and Inter-dot Spin Exchange in a Double Quantum Dot
• Singlet-triplet decoherence due to nuclear spins in a double quantum dot
• Long-range coherent coupling in a quantum dot array
• Interlaced Dynamical Decoupling and Coherent Operation of a Singlet-Triplet Qubit
• Universal set of quantum gates for double-dot spin qubits with fixed interdot coupling
• Spin-Orbit Coupling, Antilocalization, and Parallel Magnetic Fields in Quantum Dots
• Cancellation of Spin-Orbit Effects in Quantum Gates Based on the Exchange Coupling in Quantum Dots
• Hyperfine interactions in silicon quantum dots
• Noise-resistant control for a spin qubit array
• Singlet-triplet splitting in double quantum dots due to spin orbit and hyperfine interactions
• Spin-Orbit Coupling and Time-Reversal Symmetry in Quantum Gates
• Coherence and Screening in Multi-Electron Spin Qubits
• Exchange-based CNOT gates for singlet-triplet qubits with spin orbit interaction
• Dynamic Nuclear Polarization in Double Quantum Dots
• Spin-flip phonon-mediated charge relaxation in double quantum dots
• Photon- and phonon-assisted tunneling in the three-dimensional charge stability diagram of a triple quantum dot array
• The theory of coherent dynamic nuclear polarization in quantum dots

Cited by in corpus (35)

• Three-electron spin qubits
• Coherent spin-exchange via a quantum mediator
• Spin-orbit Interactions for Singlet-Triplet Qubits in Silicon
• Fast spin exchange between two distant quantum dots
• Exchange-based two-qubit gate for singlet-triplet qubits
• Negative spin exchange in a multielectron quantum dot
• Exchange coupling in a linear chain of three quantum-dot spin qubits in silicon
• Transport Spectroscopy of a Spin-Coherent Dot-Cavity System
• Spin of a multielectron quantum dot and its interaction with a neighboring electron
• High-fidelity gate set for exchange-coupled singlet-triplet qubits
• Long-range entanglement for spin qubits via quantum Hall edge modes
• High-fidelity two-qubit gates of hybrid superconducting-semiconducting singlet-triplet qubits
• Two-Qubit Pulse Gate for the Three-Electron Double Quantum Dot Qubit
• Fault-Tolerant Quantum Computation for Singlet-Triplet Qubits with Leakage Errors
• Coherent transport of spin by adiabatic passage in quantum dot arrays
• Capacitively coupled singlet-triplet qubits in the double charge resonant regime
• Negative exchange interactions in coupled few-electron quantum dots
• Jellybean quantum dots in silicon for qubit coupling and on-chip quantum chemistry
• Device Architecture for Coupling Spin Qubits Via an Intermediate Quantum State
• A Silicon Surface Code Architecture Resilient Against Leakage Errors
• Interplay of exchange and superexchange in triple quantum dots
• Cavity-mediated coherent coupling between distant quantum dots
• Characterisation of an exchange-based two-qubit gate for resonant exchange qubits
• Simple operation sequences to couple and interchange quantum information between spin qubits of different kinds
• Towards a realistic GaAs-spin qubit device for a classical error-corrected quantum memory
• Self assembled Wigner crystals as mediators of spin currents and quantum information
• Tunable charge qubit based on barrier-controlled triple quantum dots
• Controlled-NOT gate sequences for mixed spin qubit architectures in a noisy environment
• Charge noise suppression in capacitively coupled singlet-triplet spin qubits under magnetic field
• Robust entangling gate for capacitively coupled few-electron singlet-triplet qubits
• Energy spectrum, exchange interaction and gate crosstalk in a pair of double-quantum-dot system: a molecular orbital calculation
• Electron spin-flip correlations due to nuclear dynamics in driven GaAs double dots
• Two-qubit logical operations in three quantum dots system
• Noise suppression and long-range exchange coupling for gallium arsenide spin qubits
• Measurement enhances long-distance Entanglement generation in spin chains with dissipative processes