TR12 centers in diamond as a room temperature atomic scale vector magnetometer
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2022-06-02 |
| Journal | npj Quantum Information |
| Authors | Jonas Foglszinger, Andrej Denisenko, Thomas Kornher, M. Schreck, Wolfgang Knolle |
| Institutions | University of Augsburg, Centre National de la Recherche Scientifique |
| Citations | 13 |
| Analysis | Full AI Review Included |
TR12 Centers in Diamond: Room Temperature Vector Magnetometry
Section titled âTR12 Centers in Diamond: Room Temperature Vector MagnetometryâExecutive Summary
Section titled âExecutive SummaryâTR12 defects in diamond are presented as a robust, room-temperature alternative to Nitrogen-Vacancy (NV) centers for atomic-scale magnetometry, specifically addressing limitations in high-field, arbitrary-orientation sensing.
- Vector Magnetometry: TR12 centers enable full vector magnetometry under ambient conditions, unlike NV centers which are highly sensitive only along their symmetry axis.
- High Field Tolerance: The defect maintains strong Optically Detected Magnetic Resonance (ODMR) contrast (up to 30%) even when exposed to strong, off-axis magnetic fields up to 1 T and beyond.
- Spin Mechanism: The sensing relies on coherent control of a metastable excited triplet state (S=1) with long microsecond-range lifetimes (e.g., Ïx = 8.3 ”s, Ïy = 7.4 ”s).
- Sensitivity: The estimated shot-noise limited magnetic sensitivity for a single TR12 center is 3.9 ”T Hz-1/2.
- Defect Structure: TR12 exhibits twelve inequivalent orientations in the diamond lattice, ensuring that at least two orientations are always optimally aligned for vector sensing in bulk measurements.
- Jahn-Teller Effect: The defect displays a static Jahn-Teller distortion, causing switching between two spatial configurations, which manifests as anomalous splitting of ODMR lines in an external magnetic field.
- Fabrication: TR12 centers can be artificially created via standard methods (ion implantation or electron irradiation), facilitating integration into engineered diamond devices.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Operating Temperature | Room | °C | Ambient conditions |
| Maximum Field Tolerance | 1 and beyond | T | Maintains contrast at high, arbitrary fields |
| Zero Phonon Line (ZPL) | 471 | nm | Optical transition wavelength |
| Excitation Wavelength | 410 | nm | Linear polarized laser |
| Zero-Field Splitting (D) | 1636.6 | MHz | Triplet state (S=1) |
| Zero-Field Splitting (E) | 896.6 | MHz | Triplet state (S=1) |
| Excited Singlet Lifetime (ÏS1) | 4.69 | ns | Emitting state lifetime |
| Long-Lived Triplet Lifetime (Ïmeta) | 6.79 | ”s | Overall metastable decay (Tx and Ty combined) |
| Short-Lived Triplet Lifetime (Ïz) | 375 | ns | Fitted from Rabi oscillation decay |
| ODMR Contrast (Max) | Up to 30 | % | Observed in zero magnetic field |
| Shot-Noise Sensitivity (η) | 3.9 ”T Hz-1/2 | ”T Hz-1/2 | Estimated for single center (1 MHz linewidth) |
| Magnetic Field Shift (CM) | 28 | GHz per T | Frequency shift of ODMR resonance |
Key Methodologies
Section titled âKey MethodologiesâThe TR12 centers were created and characterized using standard diamond defect engineering and advanced confocal microscopy techniques.
- Substrate Preparation: Experiments utilized Chemical Vapor Deposition (CVD) diamond samples oriented along the (100) plane.
- Defect Creation (Option 1: Ion Implantation): TR12 centers were created using 12C ion implantation at energies of 10 keV or 370 keV, with a dose of 1011 ions per cm2.
- Defect Creation (Option 2: Electron Irradiation): Alternatively, defects were created using 10 MeV electron irradiation at a dose of 5 x 1016 e per cm2.
- Thermal Processing: All samples underwent post-irradiation/implantation annealing at 800 °C for 1 hour to activate the defects.
- Optical Characterization: A home-built confocal microscope was used for spectroscopic studies, employing a 410 nm linear polarized laser for excitation.
- Microwave Delivery: Spin control was achieved using microwave radiation supplied to the sample via a lithographically defined golden microwave waveguide placed on the diamond surface.
- Magnetic Field Control: A permanent magnet (NdFeB, 1.4 T magnetization) was positioned above the sample using high-precision stepper motors, allowing for continuous variation of the magnetic field magnitude and orientation relative to the defect.
Commercial Applications
Section titled âCommercial ApplicationsâThe unique properties of TR12 centersâroom-temperature operation, high-field tolerance, and vector sensing capabilityâmake them highly relevant for several high-tech sectors.
- Quantum Sensing and Metrology:
- Nanoscale Vector Magnetometry: Enabling full 3D magnetic field mapping with nanoscale spatial resolution in complex environments where field orientation is arbitrary.
- High-Field Calibration: Precise calibration and monitoring of strong magnetic fields, such as those used in advanced Magnetic Resonance Imaging (MRI) scanners or high-power industrial equipment.
- Strain and Temperature Sensing: Potential for sensing local strain and temperature at the nanoscale, though responsivity requires further assessment.
- Solid-State Quantum Information Processing (QIP):
- Nuclear Spin Readout: Utilizing the triplet state for initializing and reading out nearby nuclear spin qubits (e.g., 13C), potentially offering longer nuclear memory lifetimes due to the spin-free ground state.
- Quantum Interfaces: Serving as a robust quantum interface between stationary qubits (nuclear spins) and flying qubits (photons) when integrated into photonic crystal microcavities (Purcell enhancement).
- Advanced Materials and Defect Engineering:
- Diamond Electronics: Expanding the family of robust, optically active spin defects available for integration into diamond-based quantum devices and sensors.
- Fundamental Physics: Studying complex electronic-vibrational coupling phenomena, such as the static Jahn-Teller effect, in a solid-state host.