Characterizing gate operations near the sweet spot of an exchange-only qubit

Abstract

Optimal working points or "sweet spots" have arisen as an important tool for mitigating charge noise in quantum dot logical spin qubits. The exchange-only qubit provides an ideal system for studying this effect because $Z$ rotations are performed directly at the sweet spot, while $X$ rotations are not. Here for the first time we quantify the ability of the sweet spot to mitigate charge noise by treating $X$ and $Z$ rotations on an equal footing. Specifically, we optimize $X$ rotations and determine an upper bound on their fidelity. We find that sweet spots offer a fidelity improvement factor of at least 20 for typical GaAs devices, and more for Si devices.

10 pages

References in corpus (7)

• Electrometry Using Coherent Exchange Oscillations in a Singlet-Triplet-Qubit
• Coherent spin manipulation in an exchange-only qubit
• Singlet-triplet decoherence due to nuclear spins in a double quantum dot
• Dephasing of solid-state qubits at optimal points
• Universal set of quantum gates for double-dot spin qubits with fixed interdot coupling
• Decoherence of a Driven Qubit
• Decoherence of an exchange qubit by hyperfine interaction

Cited by in corpus (28)

• Reduced sensitivity to charge noise in semiconductor spin qubits via symmetric operation
• Noise suppression using symmetric exchange gates in spin qubits
• Three-electron spin qubits
• Extending the coherence of a quantum dot hybrid qubit
• Charge-noise-insensitive gate operations for always-on, exchange-only qubits
• Entangling distant resonant exchange qubits via circuit quantum electrodynamics
• Coupling of three-spin qubits to their electric environment
• An electrically driven spin qubit based on valley mixing
• The asymmetric resonant exchange qubit under the influence of electrical noise
• A quadrupolar exchange-only spin qubit
• Long distance coupling of resonant exchange qubits
• Optimal quantum operations at zero energy cost
• Spin blockade and coherent dynamics of high-spin states in a three-electron double quantum dot
• Realization of a $C{Q}_3$ Qubit: energy spectroscopy and coherence
• Signatures of atomic-scale structure in the energy dispersion and coherence of a Si quantum-dot qubit
• Theory of barrier vs tilt exchange gate operations in spin-based quantum computing
• Cavity-mediated entanglement of parametrically driven spin qubits via sidebands
• Coherent long-range transfer of two-electron states in ac-driven triple quantum dots
• Characterisation of an exchange-based two-qubit gate for resonant exchange qubits
• Protected Solid-State Qubits
• Photo-assisted spin transport in double quantum dots with spin-orbit interaction
• Hyperfine-induced dephasing in three-electron spin qubits
• Benchmarking of dynamically corrected gates for the exchange-only spin qubit in $1/f$ noise environment
• Coherent transfer of singlet-triplet qubit states in an architecture of triple quantum dots
• High-fidelity two-qubit gates via dynamical decoupling of local 1/f noise at optimal point
• Dynamical second-order noise sweetspots in resonantly driven spin qubits
• Two-qubit sweet spots for capacitively coupled exchange-only spin qubits
• Landau-Zener Transitions in Spin Qubit Encoded in Three Quantum Dots