Electric- field noise from carbon-adatom diffusion on a Au(110) surface: first-principles calculations and experiments

Published

March 9, 2017

Author(s)

E. Kim, Arghavan Safavi-Naini, Kyle McKay, David P. Pappas, P.F Weck, H.R. Sadeghpour, Dustin Hite

Abstract

The decoherence of trapped-ion quantum bits due to heating of their motional modes is a fundamental science and engineering problem. This heating is attributed to electric- field noise arising from processes on the trap-electrode surfaces. In this work, we address the source of this noise by focusing on the diffusion of carbon-containing adsorbates on the surface of Au(110). We show by density functional theory, based on detailed scanning probe microscopy, how the carbon adatom diffusion on the gold surface changes the energy landscape, and how the adatom dipole moment varies with the diffusive motion. A simple model for the diffusion noise, which varies quadratically with the variation of the dipole moment, qualitatively reproduces the measured noise spectrum, and the estimate of the noise spectral density is in accord with measured values.

Citation

Physical Review A (Atomic, Molecular and Optical Physics)

Pub Type

Journals

Download Paper

Local Download

Citation

Kim, E. , Safavi-Naini, A. , McKay, K. , Pappas, D. , Weck, P. , Sadeghpour, H. and Hite, D. (2017), Electric- field noise from carbon-adatom diffusion on a Au(110) surface: first-principles calculations and experiments, Physical Review A (Atomic, Molecular and Optical Physics), [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=921996 (Accessed October 8, 2025)