Single tin-vacancy center in nanoscale diamond
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2025-05-14 |
| Journal | Discover Nano |
| Authors | Masanori Fujiwara, Masanao Ohori, Frederick T.-K. So, Yuto Makino, Naoya Morioka |
| Institutions | Kyoto University Institute for Chemical Research, Daicel (Japan) |
| Citations | 2 |
| Analysis | Full AI Review Included |
Technical Analysis and Documentation: Single Tin-Vacancy Center in Nanoscale Diamond
Section titled âTechnical Analysis and Documentation: Single Tin-Vacancy Center in Nanoscale DiamondâThis document analyzes the research paper âSingle tin-vacancy center in nanoscale diamondâ and provides technical documentation, cross-referenced with 6CCVDâs advanced MPCVD diamond capabilities, to support researchers and drive sales of high-purity diamond materials.
Executive Summary
Section titled âExecutive SummaryâThe research successfully demonstrates the generation and characterization of single tin-vacancy (SnV) color centers within ultra-small detonation nanodiamonds (DNDs), opening new avenues for quantum and biological applications.
- Core Achievement: Confirmed the presence of single SnV centers in Sn-doped DNDs (mean particle size ~5 nm) via sharp Zero-Phonon Lines (ZPLs) at 620.3 nm.
- Single-Photon Source: Photon autocorrelation measurements confirmed single-photon emission, achieving a background-corrected $g^{(2)}(0)$ value as low as 0.27.
- Methodology Highlight: Successful SnV generation relied critically on a 3-day boiling acid treatment (130 °C) to remove residual $sp^{2}$ carbon and metal impurities, stabilizing the SnV charge state.
- Quantum Advantage: SnV centers offer a substantially longer spin coherence time at relatively high temperatures (> 1 K) compared to SiV and GeV centers, making them superior candidates for quantum memory without requiring a diluted refrigerator.
- Biological Relevance: The ultra-small size of the DNDs (~5 nm) makes them highly suitable for noninvasive introduction into living cell organelles for nanoscale sensing and thermometry.
- Material Challenge: The paper notes that the large size of the Sn atom induces substantial lattice strain, hindering proper SnV formationâa challenge best addressed using high-quality, low-strain MPCVD Single Crystal Diamond (SCD).
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the research paper detailing the material properties and experimental results:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Mean Particle Size (TEM) | 4.7 ± 1.7 | nm | Sn-doped Detonation Nanodiamonds (DNDs) |
| Mean Particle Size (XRD) | 5.9 | nm | Calculated using Scherrerâs formula |
| SnV ZPL Peak Wavelength (Average) | 620.3 ± 1.9 | nm | Zero-Phonon Line (ZPL) of SnV- |
| SnV ZPL Spectral Width (Average) | 5.7 ± 1.7 | nm | Full-width at half-maximum |
| Single-Photon Confirmation $g^{(2)}(0)$ | 0.27 | Dimensionless | Background-corrected value for Spot A |
| Excitation Laser Wavelength | 532 | nm | Confocal microscopy |
| Typical Laser Power | 200 | ”W | Measured before the objective lens |
| Critical Acid Treatment Duration | 3 | days | Boiling acid treatment under reflux |
| Critical Acid Treatment Temperature | 130 | °C | For impurity removal and surface functionalization |
| SnV Coherence Temperature | > 1 | K | Required temperature for long spin coherence time |
| Typical Photon Count Rate | 50 to 100 | kcps | For Spots A-E under 200 ”W power |
Key Methodologies
Section titled âKey MethodologiesâThe successful generation and stabilization of SnV centers in DNDs relied on precise detonation parameters and rigorous post-detonation purification processes:
- Detonation Synthesis: A mixed explosive (TNT / RDX / TPT) ratio of 59.2 / 39.6 / 1.2 (wt. %) was detonated under a CO2 atmosphere, incorporating tetraphenyltin (TPT) as the Sn dopant precursor.
- Initial Acid Purification: Detonation products were purified using a strong acid mixture (HNO3 / H2SO4 / H2O = 9 / 76 / 15 wt.%) heated to 150 °C for 5 hours.
- Alkali Treatment: Precipitates were treated with aqueous 8 M NaOH at 70 °C for 8 hours to specifically remove tin dioxides.
- Air Oxidation: Samples were air-oxidized [O2 / N2 = 4 / 96 (vol.%)] at 470 °C for 2 hours to remove residual $sp^{2}$ carbon.
- Critical 3-Day Boiling Acid Treatment: DND powder was subjected to a 3-day boiling acid treatment (130 °C under reflux) using a 12 / 76 / 12 (wt%) acid mixture to remove residual surface impurities and enhance oxygen-containing functional groups (e.g., carboxyl), which facilitates charge stabilization.
- Optical Characterization: Photoluminescence (PL) and photon autocorrelation $g^{(2)}(\tau)$ measurements were performed using a custom-built confocal microscope with 532 nm excitation and a 620 ± 5 nm band-pass filter.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research highlights the immense potential of SnV centers for quantum technology but also underscores the difficulty of generating stable SnV centers due to lattice strain. 6CCVDâs expertise in high-purity, low-strain MPCVD diamond provides the ideal platform to overcome these limitations and scale up quantum device fabrication.
Applicable Materials
Section titled âApplicable MaterialsâTo replicate or extend this research into scalable, high-coherence quantum devices, 6CCVD recommends the following materials:
- Optical Grade Single Crystal Diamond (SCD):
- Application: Ideal for maximizing SnV spin coherence time and spectral stability. The paper explicitly notes that strain hinders SnV formation; 6CCVDâs low-strain SCD provides a superior, bulk-like lattice environment compared to DNDs.
- Specifications: Available in thicknesses from 0.1 ”m up to 500 ”m, with ultra-low surface roughness (Ra < 1 nm).
- Boron-Doped Diamond (BDD):
- Application: For advanced sensing applications requiring charge state control or electrochemical functionality. BDD can be used as a conductive platform to stabilize the negative charge state (SnV-) or for integrated electrochemical sensing platforms.
- Specifications: Available in both SCD and Polycrystalline (PCD) formats up to 500 ”m thick.
Customization Potential
Section titled âCustomization Potentialâ6CCVD offers comprehensive material engineering services essential for integrating SnV emitters into functional quantum devices:
| Research Requirement | 6CCVD Customization Capability | Benefit to Researcher |
|---|---|---|
| Low-Strain Substrates | SCD plates up to 500 ”m thick with guaranteed low birefringence. | Ensures optimal quantum performance by minimizing phonon-mediated decoherence and spectral diffusion. |
| Device Integration | Custom dimensions and laser cutting services for plates/wafers up to 125mm (PCD). | Facilitates the creation of large-scale integrated photonic circuits and micro-structures (e.g., nanophotonic cavities). |
| Electrical Contacting | In-house metalization services (Au, Pt, Pd, Ti, W, Cu). | Enables the fabrication of electrical gates necessary for charge state tuning (critical for SnV- stabilization) and integration into quantum memory devices. |
| Surface Preparation | Polishing services achieving Ra < 1 nm (SCD) and Ra < 5 nm (inch-size PCD). | Provides atomically smooth surfaces required for subsequent high-fidelity ion implantation, epitaxial overgrowth, and surface functionalization (e.g., oxygen termination, as discussed in the paper). |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in MPCVD growth and defect engineering. We can assist researchers transitioning from DNDs to bulk or thin-film MPCVD diamond for enhanced performance in quantum memory and nanoscale thermometry projects. Our expertise ensures optimal material selection and preparation for controlled SnV creation via ion implantation or delta doping techniques.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.