NV nanodiamond doped fiber for magnetic field mapping
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2023-01-01 |
| Journal | EPJ Web of Conferences |
| Authors | Adam Filipkowski, Mariusz MrĂłzek, Grzegorz StÄpniewski, Mateusz Ficek, Dariusz Pysz |
| Institutions | GdaĆsk University of Technology, Jagiellonian University |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: NV Nanodiamond Doped Fiber for Magnetic Field Mapping
Section titled âTechnical Documentation & Analysis: NV Nanodiamond Doped Fiber for Magnetic Field MappingâThis document analyzes the research paper âNV nanodiamond doped fiber for magnetic field mappingâ (EPJ Web of Conferences 287, 10002, 2023) to highlight key technical achievements and propose specific material solutions available through 6CCVD.
Executive Summary
Section titled âExecutive SummaryâThe research successfully demonstrates distributed magnetic field sensing using nitrogen-vacancy (NV) centers volumetrically incorporated into an optical fiber core. This breakthrough enables remote, spatially-resolved magnetic field mapping, crucial for spintronics and quantum computing applications.
- Core Achievement: Demonstrated distributed magnetic field sensing and source localization over a 13 cm fiber length using remote optical readout of NV spin states.
- Material Integration: NV-rich nanodiamond particles (750 nm mean size) were volumetrically incorporated into a 50 ”m diameter multimode fiber core using a modified stack-and-draw method.
- Sensing Mechanism: Optically Detected Magnetic Resonance (ODMR) spectra were recorded at the fiber output while a localized microwave (MW) antenna was scanned along the fiber length.
- Remote Readout: Proved that localized spin information can be preserved and transmitted through a macroscopic, lossy, and noisy waveguide (fiber) for remote detection.
- Spatial Resolution: Achieved spatial resolution by physically displacing the MW perturbation, allowing for localization of the magnetic field source.
- Sensitivity: Measured magnetic field sensitivity of 26.6 ”T/âHz, demonstrating the viability of this approach for distributed sensing, despite the low ODMR contrast (< 0.1%).
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the experimental setup and results:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Diamond Particle Size (Mean) | 750 | nm | NV-rich nanodiamonds used for doping. |
| Fiber Core Diameter | 50 | ”m | Multimode fiber core containing nanodiamonds. |
| Fiber Length (Total) | 35 | cm | Total length of the fiber used in the experiment. |
| Scanning Length | 13 | cm | Section of the fiber scanned by the MW antenna. |
| Scanning Step Size | 5 | mm | Incremental step size for ODMR spectrum recording. |
| Excitation Wavelength | 532 | nm | Laser pump wavelength for NV center excitation. |
| Fluorescence Collection Range | 600 to 850 | nm | Wavelength range collected via high-pass filter. |
| Attenuation (@ 780 nm) | ~50 | dB/m | High loss characteristic of the doped fiber. |
| Magnetic Field Sensitivity | 26.6 | ”T/âHz | Measured sensitivity of the distributed sensor. |
| ODMR Contrast | < 0.1 | % | Low contrast due to localized MW application. |
| MW Antenna Width | 3 | mm | Width of the resonant antenna used for scanning. |
Key Methodologies
Section titled âKey MethodologiesâThe experiment relied on specialized material fabrication and precise optical/microwave manipulation:
- Nanodiamond Preparation: NV-rich nanodiamonds (750 nm mean size) were suspended for dip-coating.
- Fiber Preform Fabrication: A glass rod (F2 glass) was dip-coated in the nanodiamond suspension.
- Stack-and-Draw Method: The coated rod (30 mm diameter) was drawn down into 0.5 mm canes. 790 canes were stacked into a core preform, inserted into a lower refractive index glass tube, and drawn into the final multimode fiber (50 ”m core).
- Optical Pumping: The fiber was pumped with a 532 nm laser at one end.
- Fluorescence Collection: Fluorescence was collected at the opposite end (600 nm to 850 nm) through a high-pass filter.
- MW Application: A 3 mm wide MW resonant antenna, connected to a generator, was mounted on a translation stage.
- Distributed Sensing: The MW antenna was scanned along the 13 cm fiber section in 5 mm steps, applying the MW field locally to perturb the NV spin state.
- ODMR Mapping: Individual ODMR spectra were recorded at the fiber output for each position, generating a contour map that correlated frequency shift (magnetic field) with spatial position.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful demonstration of distributed sensing using NV centers opens significant avenues for commercialization. While this paper utilized nanodiamonds, future high-performance, low-noise, and integrated sensor designs will require high-purity, low-strain Single Crystal Diamond (SCD) or customized Polycrystalline Diamond (PCD) plates.
6CCVD is uniquely positioned to supply the advanced diamond materials and processing required to replicate or extend this research into robust commercial devices.
Applicable Materials for Advanced NV Sensing
Section titled âApplicable Materials for Advanced NV Sensingâ| 6CCVD Material | Application Relevance | Customization Potential |
|---|---|---|
| Optical Grade SCD | Ideal for maximizing NV coherence time and minimizing strain-induced noise, crucial for achieving fT-level sensitivities mentioned in the paperâs introduction. | Available in thicknesses from 0.1 ”m to 500 ”m, perfect for thin-film integration or high-purity substrates. |
| High-Purity PCD | Suitable for large-area sensor arrays or substrates requiring robust mechanical properties and uniform NV distribution via implantation. | Plates/wafers up to 125 mm diameter, allowing for mass production of sensor components. |
| Custom BDD (Boron-Doped Diamond) | While not directly used for NV sensing, BDD is critical for integrated electronics (e.g., on-chip MW generation or high-speed detectors) adjacent to the NV sensor. | Available for custom conductivity requirements (heavy or light doping). |
Customization Potential for Integrated Sensors
Section titled âCustomization Potential for Integrated SensorsâThe paper notes that future improvements could involve integrating the MW antenna directly with the fiber. 6CCVD offers comprehensive processing capabilities essential for such integration:
- Custom Dimensions: We provide precision laser cutting and shaping of SCD and PCD plates to create micro-machined chips or nanobeams for fiber tip embedding, replicating the high-sensitivity devices mentioned in the literature review.
- Capability: Plates/wafers up to 125 mm (PCD) and custom substrates up to 10 mm thick.
- Ultra-Low Roughness Polishing: For optimal optical coupling and minimal scattering loss when embedding diamond chips or nanobeams onto fiber tips.
- Capability: SCD polishing to Ra < 1 nm; Inch-size PCD polishing to Ra < 5 nm.
- Custom Metalization: Integration of MW antennas or electrical contacts requires precise, high-quality metal deposition.
- Capability: Internal metalization services including Au, Pt, Pd, Ti, W, and Cu, tailored for specific microwave or electrical contact requirements.
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in MPCVD growth parameters, defect engineering, and surface termination. We can assist researchers and engineers working on similar Distributed Magnetic Field Sensing projects by providing:
- Material Selection Consultation: Guidance on choosing between SCD and PCD based on required coherence time, size, and cost constraints.
- NV Center Optimization: Consultation on achieving optimal NV concentration and minimizing strain for high-fidelity quantum sensing applications.
- Custom Fabrication Design: Support in designing diamond components (e.g., micro-machined chips or thin films) for integration into complex optical systems like fiber cores or tips.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
The advances in fluorescent diamond-based magnetic field sensors have led this technology into the field of fiber optics. Recently, devices employing diamond nanobeams or diamond chips embedded on an optical fiber tip enabled achieving fT-level sensitivities. Nevertheless, these demonstrations were still confined to operation over localized magnetic field sources. A new approach of volumetric incorporation of nanodiamonds into the optical fiber core enables optical fibers sensitive to magnetic field at any point along the fiber length. We show that information on the perturbed spin state of a diamond nitrogen-vacancy color center can be transmitted over a macroscopic length in an optical fiber, in presence of noise from large concentration of the color centers along the fiber. This is exploited in optical readout at the fiber output not only of the magnetic field value, but also spatially variable information on the field, which enables the localization of its source.