Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Valley Phase and Voltage Control of Coherent Manipulation in Si Quantum Dots



Neil M. Zimmerman, Peihao Huang, Dimitrie Culcer


With any roughness at the interface of an indirect-bandgap semiconducting dot, the phase of the valley-orbit coupling can take on a random value. This random value, in double quantum dots, causes a large change in the exchange splitting. We demonstrate a simple analytical method to calculate the phase, and thus the exchange splitting and singlet−triplet qubit frequency, for an arbitrary interface. We then show that, with lateral control of the position of a quantum dot using a gate voltage, the valley−orbit phase can be controlled over a wide range, so that variations in the exchange splitting can be controlled for individual devices. Finally, we suggest experiments to measure the valley phase and the concomitant gate voltage control.
Nano Letters


Si valley, phase, voltage control


Zimmerman, N. , Huang, P. and Culcer, D. (2017), Valley Phase and Voltage Control of Coherent Manipulation in Si Quantum Dots, Nano Letters, [online], (Accessed June 19, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created June 28, 2017, Updated November 10, 2018