Journal Article

Single-shot readout of an electron spin in silicon

Zwanenburg, Floris A., Nugroho, Christopher D., Clark, Robert G., Tan, Kuan Y., Huebl, Hans, Yang, Changyi, Pla, Jarryd J., Chan, Kok W., van Donkelaar, Jessica A., Alves, Andrew D. C., Dzurak, Andrew S., Escott, Christopher C., Jamieson, David N., Morello, Andrea, Hollenberg, Lloyd C. L., Möttönen, Mikko

2010

Overview

Taking aim at silicon Silicon transistors in microelectronics are shrinking to close to the size at which quantum effects begin to have an impact on device performance. As silicon looks certain to remain the semiconductor material of choice for a while yet, such effects may be turned into an advantage by designing silicon devices that can process quantum information. One approach is to make use of electron spins generated by phosphorus dopant atoms buried in silicon, as they are known to represent well-isolated quantum bits (qubits) with long coherence times. It has not been possible to control single electrons in silicon with the precision for qubits, but now Andrea Morello and colleagues report single-shot, time-resolved readout of electron spins in silicon. This is achieved by placing the phosphorus donor atoms near a charge-sensing device called a single-electron transistor, which is fully compatible with current microelectronic technology. The demonstrated high-fidelity single-shot spin readout opens a path to the development of a new generation of quantum computing and spintronic devices in silicon. Electron spins generated by phosphorus dopant atoms buried in silicon represent well-isolated quantum bits with long coherence times, but so far the control of such single electrons has been insufficient to use them in this way. These authors report single-shot, time-resolved readout of electron spins in silicon, achieved by coupling the donor atoms to a charge-sensing device called a single-electron transistor. This opens a path to the development of a new generation of quantum computing and spintronic devices in silicon. The size of silicon transistors used in microelectronic devices is shrinking to the level at which quantum effects become important 1 . Although this presents a significant challenge for the further scaling of microprocessors, it provides the potential for radical innovations in the form of spin-based quantum computers 2 , 3 , 4 and spintronic devices 5 . An electron spin in silicon can represent a well-isolated quantum bit with long coherence times 6 because of the weak spin–orbit coupling 7 and the possibility of eliminating nuclear spins from the bulk crystal 8 . However, the control of single electrons in silicon has proved challenging, and so far the observation and manipulation of a single spin has been impossible. Here we report the demonstration of single-shot, time-resolved readout of an electron spin in silicon. This has been performed in a device consisting of implanted phosphorus donors 9 coupled to a metal-oxide-semiconductor single-electron transistor 10 , 11 —compatible with current microelectronic technology. We observed a spin lifetime of ∼6 seconds at a magnetic field of 1.5 tesla, and achieved a spin readout fidelity better than 90 per cent. High-fidelity single-shot spin readout in silicon opens the way to the development of a new generation of quantum computing and spintronic devices, built using the most important material in the semiconductor industry.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 639/766/119/1001 / 639/766/25 / Applied sciences / Atomic properties / Devices / Electron spin / Electronics / Exact sciences and technology / Humanities and Social Sciences / Integrated circuits / Integrated circuits by function (including memories and processors) / letter / Magnetic fields / Magnetoelectric, magnetostrictive, magnetoacoustic, magnetooptic and magnetothermal devices. Spintronics / Microelectronics / Microprocessors / Molecular electronics, nanoelectronics / multidisciplinary / Printed circuit boards / Science / Science (multidisciplinary) / Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices / Semiconductors / Silicon / Silicon transistors / Single electrons / Spintronics / Temperature / Transistors