Optically detected magnetic resonance of nitrogen vacancies in a diamond anvil cell using designer diamond anvils

At a Glance

Metadata	Details
Publication Date	2017-11-27
Journal	Applied Physics Letters
Authors	L. G. Steele, M. Lawson, M. Onyszczak, B. T. Bush, Z. Mei
Institutions	University of Alabama at Birmingham, Lawrence Livermore National Laboratory
Citations	32
Analysis	Full AI Review Included

Optically Detected Magnetic Resonance in Designer Diamond Anvils

Analysis of High-Pressure NV Center Magnetometry using 6CCVD Materials

This documentation summarizes the technical requirements and achievements of the research paper “Optically detected magnetic resonance of nitrogen vacancies in a diamond anvil cell using designer diamond anvils.” It highlights how 6CCVD’s specialized Microwave Plasma Chemical Vapor Deposition (MPCVD) diamond materials and processing capabilities are uniquely suited to replicate, scale, and advance this cutting-edge high-pressure quantum sensing technology.

Executive Summary

A high-density outline of the research paper’s core achievement and engineering significance:

Superior Microwave Delivery: Achieved highly efficient Optically Detected Magnetic Resonance (ODMR) of NV^- centers in a Diamond Anvil Cell (DAC) by integrating the microwave antenna directly into the diamond anvil structure.
Designer Anvil Fabrication: Utilized lithographic deposition of metallic microchannels (Tungsten, W) onto the diamond culet, followed by the growth of a protective synthetic CVD diamond layer (~50 µm thick).
High-Pressure Quantum Sensing: Successfully detected spin resonance and measured the pressure dependence of Zero-Field Splitting (ZFS) parameters (D and E) up to 8 GPa, enabling diamond to function as an effective internal manometer.
Elimination of Technical Barriers: The approach avoids the common technical challenges of high-pressure ODMR, such as low signal-to-noise ratio from external coils or fragile insulated leads required for coils placed within the gasket.
Future Application Potential: Enables microscopic Nuclear Magnetic Resonance (NMR) and vector magnetization measurements on sub-µL sample volumes at extreme high pressures, paving the way for research into materials like superconducting sulfur hydride and metallic hydrogen.

Technical Specifications

Key data points extracted from the experimental configuration and results:

Parameter	Value	Unit	Context
Pressure Measurement Range	0 to 8	GPa	ODMR effectiveness as manometer
Anvil Culet Diameter	1	mm	DAC configuration
Designer Diamond Layer Thickness	~ 50	µm	Protective CVD layer over antenna
Microwave Antenna Material	Tungsten (W), Platinum (Pt) leads	N/A	Lithographically defined microchannels
Microchannel Dimensions	8 concentric rings, 5 µm width	µm	Antenna geometry
Laser Excitation Wavelength	532	nm	NV^- center photoluminescence
Laser Power	4.5	mW	Used in optical setup
Sensing Material	15	µm	Average diameter of ensemble microdiamonds
ZFS Parameter D Pressure Slope (dD/dP)	11.72 ± 0.68	MH/GPa	Linear dependence observed
ODMR Sensitivity Target	nT/√Hz	N/A	NV center theoretical sensitivity
Sample Volume	Sub-µL	N/A	Volume limit for high-pressure experiments

Key Methodologies

A concise sequence outlining the fabrication of the designer anvils and the experimental setup:

Diamond Selection: Type Ia gem-quality diamonds with 1 mm diameter culets were selected for use as the DAC anvils.
Microchannel Fabrication (Metalization): A Tungsten (W) metal pattern, consisting of several concentric rings, was lithographically deposited onto the culet face to function as the microwave antenna.
Encapsulation via MPCVD: A high-quality, synthetic diamond layer was grown via CVD to a thickness of approximately 50 µm, completely covering and protecting the underlying W microchannels and providing a smooth contact surface.
Electrical Interconnects: Thin Platinum (Pt) wires and silver paint were used to connect the W surface antenna to external frequency source (HP 8665A).
Gasket Preparation: A 300 µm diameter hole was micro-EDM drilled into an MP35N steel gasket, followed by pre-indenting to 100 µm thickness.
Pressure Medium: Daphne oil 7373 was used as the pressure medium, with a 40 µm ruby chip included for external pressure calibration.
ODMR Setup: The 532 nm laser beam was focused to a ~10 µm spot size to excite the NV^- centers within the microdiamond sample ensemble, and the resulting fluorescence was detected by an avalanche photodiode and lock-in amplifier system.

6CCVD Solutions & Capabilities

6CCVD provides the specialized MPCVD diamond substrates, custom fabrication, and engineering expertise required to manufacture these advanced quantum sensing components. We offer solutions that meet or exceed the material specifications utilized in this pioneering research.

Applicable Materials for Replication and Extension

Application Requirement	6CCVD Material Specification	Rationale for Selection
Anvil Core Material	Optical Grade SCD (Single Crystal Diamond)	Required for high optical transparency (532 nm laser excitation) and high mechanical strength necessary for multi-GPa environments.
Protective/Passivation Layer	High-Purity SCD (0.1 µm - 500 µm)	Perfect control over the required ~50 µm thickness. Our CVD process ensures the epitaxial quality needed to protect the antenna layer without compromising NV center performance.
NV Center Integration	Tailored Nitrogen Concentration SCD	We can supply SCD materials with controlled nitrogen incorporation during growth, or high-purity SCD for post-processing techniques (e.g., implantation) to optimize NV^- center density for enhanced magnetic sensitivity.
Advanced Sensing	Boron-Doped Diamond (BDD)	For extending the research beyond NV sensing, our BDD film capabilities are essential for electrochemical and general high-pressure conductivity experiments.

Customization Potential for Designer Anvils

The success of this experiment relies entirely on the precise integration of conductive materials and diamond growth. 6CCVD’s in-house capabilities directly match these specialized needs:

Integrated Metalization Services: 6CCVD offers expert metal deposition of various materials, including Tungsten (W), Platinum (Pt), Titanium (Ti), and Gold (Au). This service enables researchers to replicate the critical W microchannel antenna and optimize the conductivity and adhesion for lithographic patterning.
Precision Thickness Control: We routinely grow synthetic diamond layers with thickness precision from 0.1 µm up to 500 µm, ensuring the exact 50 µm encapsulation layer required for structural integrity and electrical isolation can be achieved reliably.
Custom Dimensions and Finishing: Although the paper used 1 mm culets, 6CCVD can supply large, inch-size diamond plates (up to 125 mm PCD) as the base material. We offer ultra-smooth polishing services (Ra < 1 nm for SCD) crucial for subsequent photolithographic patterning and reliable high-pressure operation.

Engineering Support & Global Reach

6CCVD’s in-house PhD team can assist engineers and scientists in optimizing material selection and growth parameters for high-pressure quantum magnetometry and similar DAC projects. We provide technical consultation on selecting the optimal diamond type (SCD vs. PCD), controlling NV density, and designing robust metalization schemes suitable for extreme pressure applications.

We offer reliable Global Shipping (DDU default, DDP available) for all custom diamond substrates and specialized components, ensuring prompt delivery for time-critical research.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.

View Original Abstract

Optically detected magnetic resonance of nitrogen vacancy centers in diamond offers a route to both DC and AC magnetometry in diamond anvil cells under high pressures (&gt;3 GPa). However, a serious challenge to realizing experiments has been the insertion of microwave radiation into the sample space without screening by the gasket material. We utilize designer anvils with lithographically deposited metallic microchannels on the diamond culet as a microwave antenna. We detected the spin resonance of an ensemble of microdiamonds under pressure and measured the pressure dependence of the zero field splitting parameters. These experiments enable the possibility for all-optical magnetic resonance experiments on nanoliter sample volumes at high pressures.

Tech Support

Original Source

DOI: https://doi.org/10.1063/1.5004153

References

2000 - Pressure-induced superconductivity in quasi-2D CeRhIn5 [Crossref]
2009 - Superconductivity up to 29 K in SrFe2As2 and BaFe2As2 at high pressures [Crossref]
2017 - Observation of the Wigner-Huntington transition to metallic hydrogen [Crossref]
2009 - Spontaneous formation of a superconducting and antiferromagnetic hybrid state in SrFe2As2 under high pressure [Crossref]
2015 - Evolution of hyperfine parameters across a quantum critical point in CeRhIn5 [Crossref]
2012 - 10 GPa-class high-pressure NMR technique realized by the new cell with improved space efficiency [Crossref]
2015 - High-sensitivity NMR beyond 200,000 atmospheres of pressure [Crossref]
1987 - NMR in a diamond anvil cell [Crossref]
1989 - Molecular motion in solid H2 at high pressures [Crossref]
1998 - Nuclear magnetic resonance in a diamond anvil cell at very high pressures [Crossref]