Publication
Title
Photoluminescence of germanium-vacancy centers in nanocrystalline diamond films : implications for quantum sensing applications
Author
Abstract
Point defects in diamond, promising candidates for nanoscale pressure- and temperature-sensing applications, are potentially scalable in polycrystalline diamond fabricated using the microwave plasma-enhanced chemical vapor deposition (MW PE CVD) technique. However, this approach introduces residual stress in the diamond films, leading to variations in the characteristic zero phonon line (ZPL) of the point defect in diamond. Here, we report the effect of residual stress on germanium-vacancy (GeV) centers in MW PE CVD nanocrystalline diamond (NCD) films fabricated using single crystal Ge as the substrate and solid dopant source. GeV ensemble formation indicated by the zero phonon line (ZPL) at similar to 602 nm is confirmed by room temperature (RT) photoluminescence (PL) measurements. PL mapping results show spatial nonuniformity in GeV formation along with other defects, including silicon-vacancy centers in the diamond films. The residual stress in NCD results in shifts in the PL peak positions. By estimating a stress shift coefficient of (2.9 +/- 0.9) nm/GPa, the GeV PL peak position in the NCD film is determined to be between 598.7 and 603.2 nm. A larger ground state splitting due to the strain on a GeV-incorporated NCD pillar at a low temperature (10 K) is also reported. We also report the observation of intense ZPLs at RT that in some cases could be related to low Ge concentration and the surrounding crystalline environment. In addition, we also observe thicker microcrystalline diamond (MCD) films delaminate from the Ge substrate due to film residual stress and graphitic phase at the diamond/Ge substrate interface (confirmed by electron energy loss spectroscopy). Using this approach, a free-standing color center incorporated MCD film with dimensions up to 1 x 1 cm(2) is fabricated. Qualitative analysis using time-of-flight secondary ion mass spectroscopy reveals the presence of impurities, including Ge and silicon, in the MCD film. Our experimental results will provide insights into the scalability of GeV fabrication using the MW PE CVD technique and effectively implement NCD-based nanoscale-sensing applications.
Language
English
Source (journal)
ACS applied nano materials. - Washington, DC, 2018, currens
Publication
Washington : Amer chemical soc , 2024
ISSN
2574-0970
DOI
10.1021/ACSANM.3C05491
Volume/pages
7 :4 (2024) , p. 3873-3884
ISI
001164609600001
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Project info
Hybrid spin-charge quantum systems based of single point defects in diamond: Combined theoretical and experimental approach.
Coincident event detection for advanced spectroscopy in transmission electron microscopy.
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 29.03.2024
Last edited 05.11.2024
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