Electron spin resonance from NV centers in diamonds levitating in an ion trap
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2017-03-09 |
| Journal | New Journal of Physics |
| Authors | Tom Delord, L. Nicolas, Lucien Schwab, G. HĂ©tet |
| Institutions | Université Paris Sciences et Lettres, Sorbonne Université |
| Citations | 71 |
| Analysis | Full AI Review Included |
Technical Analysis and Documentation: NV Centers in Levitating MPCVD Diamond
Section titled âTechnical Analysis and Documentation: NV Centers in Levitating MPCVD DiamondâDocument ID: 6CCVD-ANL-160502953v2 Subject: Electron Spin Resonance (ESR) in Levitating Diamond NV Centers Application Focus: Quantum Sensing, Vectorial Magnetometry, Optomechanics
Executive Summary
Section titled âExecutive SummaryâThis research successfully demonstrates the observation of high-contrast Electron Spin Resonance (ESR) in single-crystal microdiamonds hosting Nitrogen Vacancy ($\text{NV}^{-}$) centers while levitating in a Paul ion trap under ambient conditions.
- Novel Trapping Regime: The study confirms that ion traps (Paul trap) offer a scattering-free levitation method, preventing the optical quenching and excessive heating observed in traditional optical traps.
- Efficient Spin Control: Demonstrated effective microwave driving of the $\text{NV}^{-}$ electronic spin using a remote antenna ($150 \text{ ”m}$ distance), validating the materialâs suitability for quantum control schemes.
- Angular Stability Demonstrated: ESR measurements confirmed angular stability of trapped single monocrystals over time scales of minutes, a critical precursor for realizing spin-controlled levitating macroscopic objects.
- Material Inhomogeneity Identified: The HPHT diamond powders used showed highly inhomogeneous $\text{NV}^{-}$ density, varying by over two orders of magnitude, necessitating improved material control for scaling.
- Future Sensing Applications: This system establishes a pathway for applying $\text{NV}^{-}$ centers in ion traps for advanced quantum sensing, specifically mentioning vectorial magnetometry and high-precision multi-axis rotational sensing.
- Observed Charge: Estimated $\sim 5000$ elementary excess charges on the surface of a $10 \text{ ”m}$ diamond particle under typical operating conditions.
Technical Specifications
Section titled âTechnical SpecificationsâExtracted hard data points from the experimental setup and results.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Material Size Studied | 500 nm to 12 ”m | Diameter | Monocrystalline HPHT powder |
| AC Trap Voltage ($V_{\text{ac}}$) | 1000 to 4000 | V (p-p) | Peak-to-peak operating voltage of the Paul trap |
| Trapping Frequency ($\Omega/2\pi$) | $\approx 5$ | kHz | AC operating frequency of the trap electrodes |
| Axial Confinement Freq ($\omega_{\text{z}}/2\pi$) | 1 to 1.5 | kHz | Observed macromotional frequency range |
| Laser Excitation Wavelength | 532 | nm | Green laser, used for spin initialization and readout |
| Laser Power (PL/Imaging) | 100 ”W to 3.6 mW | Power | Power range used for imaging and photoluminescence |
| $\text{NV}^{-}$ ZPL Emission | 637 | nm | Zero-Phonon Line (ZPL) wavelength |
| $\text{NV}^{0}$ ZPL Emission | 575 | nm | Neutral NV ZPL wavelength |
| Applied Magnetic Field (B) | 10 to 80 | G | Field deduced from Zeeman splitting measurements |
| Total Surface Charge ($Q_{\text{tot}}$) | $\sim 5000$ | Elementary Charges | Estimated excess charge on a $10 \text{ ”m}$ diamond surface |
| Microwave Antenna Offset | 150 | ”m | Distance from antenna to trap center for ESR driving |
| SCD Surface Curvature ($\xi$) | $2 \times 10^{6}$ | V/m2 | Curvature of the static electric potential |
Key Methodologies
Section titled âKey MethodologiesâA concise sequence of the experimental procedure used to achieve levitation and spin resonance.
- Diamond Preparation: HPHT monocrystalline diamond powders (MSY micron-diamond) were used, selected for sizes up to $12 \text{ ”m}$. No specific processing was detailed, resulting in highly variable $\text{NV}^{-}$ density.
- Particle Charging & Loading: Diamond particles were charged and subsequently introduced into the trap center vicinity by first dipping a $300 \text{ ”m}$ copper wire into the powder.
- Ion Trap Operation: A needle Paul-Straubel trap, operating under ambient air conditions, was used. Confinement was achieved using an oscillating electric field up to $4000 \text{ V}$ (p-p) at $5 \text{ kHz}$.
- Position and Motion Monitoring: Particle position and rotation were tracked using phase contrast imagingâmeasuring interference between the $532 \text{ nm}$ input laser and scattered light.
- Excitation & Readout: The $\text{NV}^{-}$ centers were excited via the phonon continuum using the $532 \text{ nm}$ laser. Photoluminescence (PL) was collected through a high NA (0.77) lens, filtered (Notch filter at $532 \text{ nm}$), and detected using an avalanche photodiode (APD).
- Spin Resonance Measurement (ESR): A static magnetic field (up to $80 \text{ G}$) was applied via a permanent magnet to Zeeman shift the $\text{NV}^{-}$ levels. An external microwave antenna ($150 \text{ ”m}$ offset) provided the oscillating field necessary to drive the ESR transitions.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research validates levitating diamond quantum emitters as a viable platform for advanced sensing, particularly vectorial magnetometry and high-precision rotational sensing. 6CCVDâs advanced MPCVD materials offer the necessary control and homogeneity to advance this work beyond research limitations imposed by commercially sourced HPHT powder.
| Research Limitation / Requirement | 6CCVD Material Solution | 6CCVD Capability Enhancement |
|---|---|---|
| Inhomogeneous $\text{NV}^{-}$ Density: HPHT materials showed >2 orders of magnitude variation, severely limiting reliability. | Optical Grade SCD (Single Crystal Diamond): MPCVD allows for precise, in-situ nitrogen doping during growth, yielding uniform $\text{NV}^{-}$ concentration across large wafers, maximizing spin contrast and experimental predictability. | Controlled Doping: 6CCVD guarantees customized nitrogen concentrations to optimize for single-spin coherence time or high-density ensemble sensing. |
| Precise Particle Geometry: Future optomechanics require highly specific, non-spherical geometries (e.g., ellipses, micro-cubes) for stable rotational confinement. | Precision Laser Micromachining: We fabricate custom dimensions from high-quality MPCVD SCD/PCD wafers up to $125 \text{ mm}$. This includes laser cutting and dicing services for sub-micron particle creation or plate sizing. | Custom Dimensions: Plates/wafers up to $125 \text{ mm}$ (PCD). SCD/PCD thickness $0.1 \text{ ”m}$ to $500 \text{ ”m}$. |
| Complex Platform Integration: Future chips require integrated planar microwave lines and static magnetic field coils (for high precision control). | Advanced On-Chip Metalization: 6CCVD provides internal metalization capabilities, including deposition of Au, Pt, Pd, Ti, W, and Cu layers, enabling direct fabrication of electrodes or coplanar waveguides onto the SCD substrate. | Integrated Electrodes: Metalization services for creating robust interfaces between quantum material and trapping electronics. |
| Surface Charge Control: Surface quality directly impacts particle confinement and stability in the Paul trap, especially related to radiation pressure effects. | Ultra-Low Roughness Polishing: Our polishing standards achieve $\text{Ra} < 1 \text{ nm}$ for SCD and $\text{Ra} < 5 \text{ nm}$ for Inch-size PCD wafers, minimizing surface defects that can accumulate static charge and destabilize the trap. | Enhanced Stability: Minimizing surface roughness improves charge stability and reduces parasitic forces. |
Engineering Support and Ordering
Section titled âEngineering Support and Orderingâ6CCVD provides high-purity, low-strain Single Crystal Diamond (SCD) material, critical for achieving high-fidelity spin readout and extending the coherence times necessary for sensitive magnetometry and rotational sensing applications described in this paper.
Our in-house PhD team can assist with material selection, optimal nitrogen concentration targets, and design considerations for implementing novel spin-optomechanical or quantum sensing projects. We offer global shipping (DDU default, DDP available) for rapid delivery of custom wafers and micro-machined parts.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
We report observations of the Electron Spin Resonance (ESR) of Nitrogen\nVacancy (NV) centers in diamonds that are levitating in an ion trap. Using a\nneedle Paul trap operating under ambient conditions, we demonstrate efficient\nmicrowave driving of the electronic spin and show that the spin properties of\ndeposited diamond particles measured by the ESR are retained in the Paul trap.\nWe also exploit the ESR signal to monitor the rotation of levitating\nmonocrystals, a first step towards spin-controlled mechanical systems in\nscattering-free traps.\n