Detecting nitrogen-vacancy-hydrogen centers on the nanoscale using nitrogen-vacancy centers in diamond
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2024-02-28 |
| Journal | Physical Review Materials |
| Authors | Christoph Findler, RĂ©mi Blinder, Karolina SchĂŒle, Priyadharshini Balasubramanian, Christian Osterkamp |
| Citations | 2 |
Abstract
Section titled âAbstractâIn diamond, nitrogen defects like the substitutional nitrogen defect <a:math xmlns:a=âhttp://www.w3.org/1998/Math/MathMLâ><a:mo>(</a:mo><a:msub><a:mi mathvariant=ânormalâ>N</a:mi><a:mi mathvariant=ânormalâ>s</a:mi></a:msub><a:mo>)</a:mo></a:math> or the nitrogen-vacancy-hydrogen complex (NVH) outnumber the nitrogen-vacancy (NV) defect by at least one order of magnitude creating a dense spin bath. While neutral <d:math xmlns:d=âhttp://www.w3.org/1998/Math/MathMLâ><d:msub><d:mi mathvariant=ânormalâ>N</d:mi><d:mi mathvariant=ânormalâ>s</d:mi></d:msub></d:math> has an impact on the coherence of the NV spin state, the atomic structure of NVH reminds of a NV center decorated with a hydrogen atom. As a consequence, the formation of NVH centers could compete with that of NV centers possibly lowering the N-to-NV conversion efficiency in diamond grown with hydrogen-plasma-assisted chemical vapor deposition (CVD). Therefore, monitoring and controlling the spin bath is essential to produce and understand engineered diamond material with high NV concentrations for quantum applications. While the incorporation of <g:math xmlns:g=âhttp://www.w3.org/1998/Math/MathMLâ><g:msub><g:mi mathvariant=ânormalâ>N</g:mi><g:mi mathvariant=ânormalâ>s</g:mi></g:msub></g:math> in diamond has been investigated on the nano- and mesoscale for years, studies concerning the influence of CVD parameters and the crystal orientation on the NVH formation have been restricted to bulk N-doped diamond providing high-enough spin numbers for electron paramagnetic resonance and optical absorption spectroscopy techniques. Here, we investigate submicron-thick (100)-diamond layers with nitrogen contents of <j:math xmlns:j=âhttp://www.w3.org/1998/Math/MathMLâ><j:mrow><j:mo>(</j:mo><j:mn>13.8</j:mn><j:mo>±</j:mo><j:mn>1.6</j:mn><j:mo>)</j:mo><j:mspace width=â0.16emâ/><j:mi>ppm</j:mi></j:mrow></j:math> and <l:math xmlns:l=âhttp://www.w3.org/1998/Math/MathMLâ><l:mrow><l:mo>(</l:mo><l:mn>16.7</l:mn><l:mo>±</l:mo><l:mn>3.6</l:mn><l:mo>)</l:mo><l:mspace width=â0.16emâ/><l:mi>ppm</l:mi></l:mrow></l:math>, and exploiting the NV centers in the layers as local nanosensors, we demonstrate the detection of <n:math xmlns:n=âhttp://www.w3.org/1998/Math/MathMLâ><n:mrow><n:msup><n:mrow/><n:mrow/></n:msup><n:msup><n:mi>NVH</n:mi><n:mo>â</n:mo></n:msup></n:mrow></n:math> centers using double electron-electron resonance (DEER). To determine the <o:math xmlns:o=âhttp://www.w3.org/1998/Math/MathMLâ><o:mrow><o:msup><o:mrow/><o:mrow/></o:msup><o:msup><o:mi>NVH</o:mi><o:mo>â</o:mo></o:msup></o:mrow></o:math> densities, we quantitatively fit the hyperfine structure of <p:math xmlns:p=âhttp://www.w3.org/1998/Math/MathMLâ><p:mrow><p:msup><p:mrow/><p:mrow/></p:msup><p:msup><p:mi>NVH</p:mi><p:mo>â</p:mo></p:msup></p:mrow></p:math> and confirm the results with the DEER method usually used for determining <q:math xmlns:q=âhttp://www.w3.org/1998/Math/MathMLâ><q:mrow><q:msup><q:mrow/><q:mrow/></q:msup><q:msup><q:mrow><q:msub><q:mi mathvariant=ânormalâ>N</q:mi><q:mi mathvariant=ânormalâ>s</q:mi></q:msub></q:mrow><q:mn>0</q:mn></q:msup></q:mrow></q:math> densities. With our experiments, we access the spin bath composition on the nanoscale and enable a fast feedback loop in CVD recipe optimization with thin diamond layers instead of resource- and time-intensive bulk crystals. Furthermore, the quantification of <t:math xmlns:t=âhttp://www.w3.org/1998/Math/MathMLâ><t:mrow><t:msup><t:mrow/><t:mrow/></t:msup><t:msup><t:mi>NVH</t:mi><t:mo>â</t:mo></t:msup></t:mrow></t:math> plays a very important role for understanding the dynamics of vacancies and the incorporation of hydrogen into CVD diamond optimized for quantum technologies. Published by the American Physical Society 2024