High-Sensitivity Charge Detection with a Single-Lead Quantum Dot for Scalable Quantum Computation
Abstract
We report the development of a high-sensitivity semiconductor charge sensor based on a quantum dot coupled to a single lead designed to minimize the geometric requirements of a charge sensor for scalable quantum-computing architectures. The quantum dot is fabricated in Si:P using atomic precision lithography, and its charge transitions are measured with rf reflectometry. A second quantum dot with two leads placed 42 nm away serves as both a charge for the sensor to measure and as a conventional rf single-electron transistor (rf SET) with which to make a comparison of the charge-detection sensitivity. We demonstrate sensitivity equivalent to an integration time of 550 ns to detect a single charge with a signal-to-noise ratio of 1 compared with an integration time of 55 ns for the rf SET. This level of sensitivity is suitable for fast (<15 μ s ) single-spin readout in quantum-information applications, with a significantly reduced geometric footprint compared to the rf SET.
- Publication:
-
Physical Review Applied
- Pub Date:
- October 2016
- DOI:
- 10.1103/PhysRevApplied.6.044016
- Bibcode:
- 2016PhRvP...6d4016H