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Title: Integrating quantum groups over surfaces: INTEGRATING QUANTUM GROUPS OVER SURFACES
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Oxford University Press (OUP)
Date Published:
Journal Name:
Journal of Topology
Page Range / eLocation ID:
p. 874-917
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Abstract

    Identifying the surface chemistry of diamond materials is increasingly important for device applications, especially quantum sensors. Oxygen-related termination species are widely used because they are naturally abundant, chemically stable, and compatible with stable nitrogen vacancy centres near the diamond surface. Diamond surfaces host a mixture of oxygen-related species, and the precise chemistry and relative coverage of different species can lead to dramatically different electronic properties, with direct consequences for near-surface quantum sensors. However, it is challenging to unambiguously identify the different groups or quantify the relative surface coverage. Here we show that a combination of x-ray absorption and photoelectron spectroscopies can be used to quantitatively identify the coverage of carbonyl functional groups on the{100}diamond surface. Using this method we reveal an unexpectedly high fraction of carbonyl groups (>9%) on a wide range of sample surfaces. Furthermore, through a combination ofab initiocalculations and spectroscopic studies of engineered surfaces, we reveal unexpected complexities in the x-ray spectroscopy of oxygen terminated diamond surfaces. Of particular note, we find the binding energies of carbonyl-related groups on diamond differs significantly from other organic systems, likely resulting in previous misestimation of carbonyl fractions on diamond surfaces.

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