Temperature drift rate for nuclear terms of the NV-center ground-state Hamiltonian
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-09-18 |
| Journal | Physical review. B./Physical review. B |
| Authors | Vladimir V. Soshenko, Vadim Vorobyov, Stepan V. Bolshedvorskii, Olga R. Rubinas, I. S. Cojocaru |
| Institutions | Texas A&M University, Russian Quantum Center |
| Citations | 17 |
| Analysis | Full AI Review Included |
Executive Summary
Section titled âExecutive SummaryâThis technical documentation analyzes the research on temperature drift in Nitrogen-Vacancy (NV) centers, highlighting 6CCVDâs capability to supply the high-purity, custom diamond materials required for advanced quantum sensing applications.
- Core Achievement: Experimental measurement of the temperature-dependent shift of the 14N nuclear spin hyperfine splitting in the NV center ground state.
- Critical Finding for Sensors: A significant linear temperature shift of approximately 200 Hz/°C was observed for the nuclear spin transitions, which must be systematically accounted for in high-precision ensemble-based sensors (gyroscopes, magnetometers).
- Mechanism Identified: The shift is predominantly driven by the temperature dependence of the hyperfine constant (Fermi contact term drift), contributing -188 ± 20 Hz/°C.
- Material Requirement: The experiment utilized high-quality bulk diamond with a controlled NV concentration (approximately 1 ppm) and specific (111) crystallographic orientation.
- Methodology: The study employed Optically Detected Magnetic Resonance (ODMR) using pulsed sequences (MW $\pi$ and RF pulses) and temperature calibration via the known ODMR spectral shift (~70 kHz/K).
- Thermal Management: Significant heating (up to 60 °C) was induced by high-power 532 nm CW laser excitation (3 W), underscoring the need for robust thermal management in practical NV sensor designs.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the experimental results regarding the NV center properties and temperature sensitivity:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| NV Zero Field Splitting (D) | 2.87 | GHz | Ground state |
| Hyperfine Structure Constant (Q) | 5 | MHz | 14N nuclear spin splitting |
| ODMR Temperature Shift (Calibration) | ~70 | kHz/K | Used for sample temperature measurement |
| Total 14N Nuclear Spin Shift (âfRF/âT) | ~200 | Hz/°C | Required systematic correction in sensors |
| Hyperfine Constant Contribution (âA||/âT) | -188 ± 20 | Hz/°C | Dominant shift mechanism |
| Quadrupole Moment Contribution (âQ/âT) | -24 ± 4 | Hz/°C | Low sensitivity term |
| Laser Wavelength | 532 | nm | Optical pumping source |
| Laser Power Used | 3 | W | Focused onto 0.05 mm spot |
| Maximum Observed Heating | ~60 | °C | Due to CW laser excitation |
| Diamond NV Concentration | ~1 | ppm | Used in bulk sample |
Key Methodologies
Section titled âKey MethodologiesâThe experiment relied on precise control of optical, microwave (MW), and radio frequency (RF) fields applied to an ensemble of NV centers in a bulk diamond plate.
- Sample Preparation: Bulk diamond plate polished perpendicular to the (111) crystallographic axis, containing approximately 1 ppm of NV centers.
- Optical Excitation: 3 W, 532 nm CW laser radiation, modulated by an Acousto-Optic Modulator (AOM), focused onto a 0.05 mm spot.
- Temperature Variation: Sample temperature was varied by adjusting the duty cycle of the high-power laser, inducing heating up to 60 °C.
- Temperature Calibration: Sample temperature was calibrated by measuring the known spectral shift of the ODMR resonance position (~70 kHz/K).
- Spin Manipulation Sequence: A pulsed sequence similar to nuclear recursive polarization was used, involving:
- Green optical pump (initialization to $m_s=0$).
- MW $\pi$ pulse (transfer to $m_s=-1$ manifold).
- RF pulse (mixing hyperfine levels in the $m_s=-1$ manifold).
- Optical pulse (return population to $m_s=0$).
- Second MW $\pi$ pulse (signal suppression via ODMR).
- Detection: 2D scanning of RF and MW frequencies was performed to determine the center of the ODMR transition and measure the resulting shift of the nuclear spin resonance.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & Capabilitiesâ6CCVD is uniquely positioned to supply the high-specification MPCVD diamond required to replicate, optimize, and scale this research into commercial quantum sensors. Our materials ensure the high purity and precise crystallographic control necessary for stable NV ensemble performance.
Applicable Materials for NV Quantum Sensing
Section titled âApplicable Materials for NV Quantum SensingâThe research requires high-quality Single Crystal Diamond (SCD) with controlled nitrogen incorporation and specific orientation.
| 6CCVD Material Recommendation | Specification & Relevance |
|---|---|
| Optical Grade SCD | Required for high-power 532 nm excitation and fluorescence collection. Ensures minimal absorption and scattering losses, reducing unwanted heating. |
| Custom NV Concentration | We provide SCD with controlled nitrogen doping (precursor to NV centers) to match or optimize the 1 ppm concentration used, balancing signal strength and coherence time. |
| (111) Oriented SCD Plates | The paper explicitly used a plate polished perpendicular to the (111) axis. 6CCVD offers custom crystallographic orientations, crucial for maximizing the signal projection in specific sensor geometries (e.g., rotation sensing). |
| High Purity Substrates | SCD substrates up to 10 mm thick are available for robust thermal management, mitigating the 60 °C heating observed in the experiment. |
Customization Potential for Advanced Sensor Integration
Section titled âCustomization Potential for Advanced Sensor IntegrationâTo move from laboratory experiments to integrated devices, 6CCVD offers extensive customization capabilities that directly address the needs of quantum sensor development:
- Custom Dimensions and Thickness: We supply SCD plates from 0.1 ”m up to 500 ”m thick, and PCD plates/wafers up to 125 mm in diameter, allowing for scaling of ensemble sensors.
- Precision Polishing: Our SCD polishing achieves surface roughness (Ra) < 1 nm, essential for minimizing optical losses and ensuring high-fidelity optical coupling required for ODMR readout.
- Integrated Metalization: The experiment utilized complex external copper antennas for MW and RF delivery. 6CCVD offers in-house metalization (Au, Pt, Pd, Ti, W, Cu) for fabricating on-chip antennas and microstrip lines directly onto the diamond surface, enabling compact, high-frequency control of the NV ensemble.
- Laser Cutting and Shaping: Custom laser cutting services allow for precise shaping of the diamond plate to fit specific antenna or resonator geometries, optimizing field delivery (MW/RF) and thermal contact.
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in material science for quantum applications. We provide expert consultation to assist researchers and engineers in selecting the optimal diamond specifications (purity, orientation, doping level) for projects focused on NV-based quantum sensing, gyroscopes, and magnetic field sensors. We ensure the material properties minimize systematic errors, such as the temperature drift analyzed in this research.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Nitrogen-vacancy (NV) center in diamond was found to be a powerful tool for various sensing applications. The main work horse of this center so far has been optically detected electron resonance. Utilization of the nuclear spin has the potential of significantly improving sensitivity in rotation and magnetic field sensors. Ensemble-based sensors consume quite a bit of power, thus requiring an understanding of temperature-related shifts. In this article, we provide a detailed study of the temperature shift of the hyperfine components of the NV center.