Crystallographic orientation dependence of work function: carbon adsorption on Au surfaces

Abstract

We investigate the work function (WF) variation of different Au crystallographic surface orientations with carbon atom adsorption. Ab initio calculations within density-functional theory are performed on carbon deposited (100), (110), and (111) gold surfaces. The WF behaviour with carbon coverage for the different surface orientations is explained by the resultant electron charge density distributions. The dynamics of carbon adsorption at sub-to-one- monolayer (ML) coverage depends on the landscape of the potential energy surfaces. At higher ML coverage, because of adsorption saturation, the WF will have weak surface orientation dependence. This systematic study has consequential bearing on studies of electric-field noise emanating from polycrystalline gold ion-trap electrodes that have been largely employed in microfabricated electrodes.

GRAPHICAL ABSTRACT

Keywords:

• Surface noise
• ion trap
• surface induced electric noise
• ion trap
• quantum computing

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

HZJ is supported by a theory grant from the NIST Physical Measurement Laboratory. HRS acknowledges support from the NSF through a grant for ITAMP at Harvard University. XF conducted work as a high school intern in the summer of 2018 at ITAMP. KM is an associate in the Professional Research Experience Program (PREP) operated jointly by NIST and the University of Colorado Boulder under award 70NANB18H006 from the U.S. Department of Commerce, National Institute of Standards and Technology.