![]() Characterizing Si:P quantum dot qubits with spin resonance techniques. Wang, Y., Chen, C.-Y., Klimeck, G., Simmons, M. Highly tunable exchange in donor qubits in silicon. Exchange in silicon-based quantum computer architecture. Spin-lattice relaxation times of single donors and donor clusters in silicon. Two-electron spin correlations in precision placed donors in silicon. High-fidelity single-shot singlet-triplet readout of precision-placed donors in silicon. Single-shot correlations and two-qubit gate of solid-state spins. Charge noise spectroscopy using coherent exchange oscillations in a singlet-triplet qubit. A quantum-dot spin qubit with coherence limited by charge noise and fidelity higher than 99.9%. Spin blockade and exchange in Coulomb-confined silicon double quantum dots. Radio frequency reflectometry and charge sensing of a precision placed donor in silicon. Robust two-qubit gates for donors in silicon controlled by hyperfine interactions. Efficient controlled-phase gate for single-spin qubits in quantum dots. Fidelity benchmarks for two-qubit gates in silicon. Two-qubit gate of combined single-spin rotation and interdot spin exchange in a double quantum dot. A programmable two-qubit quantum processor in silicon. ![]() Resonantly driven CNOT gate for electron spins. Global control and fast solid-state donor electron spin quantum computing. Quantifying the quantum gate fidelity of single-atom spin qubits in silicon by randomized benchmarking. Storing quantum information for 30 seconds in a nanoelectronic device. A silicon-based nuclear spin quantum computer. By engineering qubit placement on the atomic scale, we provide a route to the realization and efficient characterization of multi-qubit quantum circuits based on donor qubits in silicon. Here we report a fast (about 800 picoseconds) \(\sqrt\) two-qubit exchange gate between phosphorus donor electron spin qubits in silicon using independent single-shot spin readout with a readout fidelity of about 94 per cent on a complete set of basis states. This is because it is difficult to determine the atomic distance required to turn the exchange interaction on and off while aligning the atomic circuitry for high-fidelity, independent spin readout. However, creating a tunable exchange interaction between two electrons bound to phosphorus atom qubits has not been possible until now. Exchange interactions between electron spins 4, 5 promise fast (gigahertz) gate operations with two-qubit gates, as recently demonstrated in gate-defined silicon quantum dots 6, 7, 8, 9, 10. However, inter-qubit coupling-which is essential for realizing large-scale circuits in atom-based qubits-has not yet been achieved. High-fidelity (more than 99.9 per cent) coherent control of such qubits has been demonstrated 3, promising an attractive platform for quantum computing. Electron spin qubits formed by atoms in silicon have large (tens of millielectronvolts) orbital energies and weak spin–orbit coupling, giving rise to isolated electron spin ground states with coherence times of seconds 1, 2.
0 Comments
Leave a Reply. |