Unraveling sources of emission heterogeneity in Silicon Vacancy color centers with cryo-cathodoluminescence microscopy
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2024-03-29 |
| Journal | Proceedings of the National Academy of Sciences |
| Authors | Daniel K. Angell, Shuo Li, Hendrik Utzat, Matti L. S. Thurston, Yin Liu |
| Institutions | SLAC National Accelerator Laboratory, Stanford University |
| Citations | 3 |
Abstract
Section titled “Abstract”Diamond color centers have proven to be versatile quantum emitters and exquisite sensors of stress, temperature, electric and magnetic fields, and biochemical processes. Among color centers, the silicon-vacancy (SiV <mml:math xmlns:mml=“http://www.w3.org/1998/Math/MathML” display=“inline” overflow=“scroll”> <mml:msup> <mml:mrow/> <mml:mo>−</mml:mo> </mml:msup> </mml:math> ) defect exhibits high brightness, minimal phonon coupling, narrow optical linewidths, and high degrees of photon indistinguishability. Yet the creation of reliable and scalable SiV <mml:math xmlns:mml=“http://www.w3.org/1998/Math/MathML” display=“inline” overflow=“scroll”> <mml:msup> <mml:mrow/> <mml:mo>−</mml:mo> </mml:msup> </mml:math> -based color centers has been hampered by heterogeneous emission, theorized to originate from surface imperfections, crystal lattice strain, defect symmetry, or other lattice impurities. Here, we advance high-resolution cryo-electron microscopy combined with cathodoluminescence spectroscopy and 4D scanning transmission electron microscopy (STEM) to elucidate the structural sources of heterogeneity in SiV <mml:math xmlns:mml=“http://www.w3.org/1998/Math/MathML” display=“inline” overflow=“scroll”> <mml:msup> <mml:mrow/> <mml:mo>−</mml:mo> </mml:msup> </mml:math> emission from nanodiamond with sub-nanometer-scale resolution. Our diamond nanoparticles are grown directly on TEM membranes from molecular-level seedings, representing the natural formation conditions of color centers in diamond. We show that individual subcrystallites within a single nanodiamond exhibit distinct zero-phonon line (ZPL) energies and differences in brightness that can vary by 0.1 meV in energy and over 70% in brightness. These changes are correlated with the atomic-scale lattice structure. We find that ZPL blue-shifts result from tensile strain, while ZPL red shifts are due to compressive strain. We also find that distinct crystallites host distinct densities of SiV <mml:math xmlns:mml=“http://www.w3.org/1998/Math/MathML” display=“inline” overflow=“scroll”> <mml:msup> <mml:mrow/> <mml:mo>−</mml:mo> </mml:msup> </mml:math> emitters and that grain boundaries impact SiV <mml:math xmlns:mml=“http://www.w3.org/1998/Math/MathML” display=“inline” overflow=“scroll”> <mml:msup> <mml:mrow/> <mml:mo>−</mml:mo> </mml:msup> </mml:math> emission significantly. Finally, we interrogate nanodiamonds as small as 40 nm in diameter and show that these diamonds exhibit no spatial change to their ZPL energy. Our work provides a foundation for atomic-scale structure-emission correlation, e.g., of single atomic defects in a range of quantum and two-dimensional materials.
Tech Support
Section titled “Tech Support”Original Source
Section titled “Original Source”References
Section titled “References”- 2014 - Isotopically varying spectral features of silicon-vacancy in diamond