All-optical control of a single electron spin in diamond
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2015-02-11 |
| Journal | Physical Review A |
| Authors | Yiwen Chu, Matthew Markham, Daniel J. Twitchen, Mikhail D. Lukin |
| Institutions | Element Six (United States), Yale University |
| Citations | 30 |
| Analysis | Full AI Review Included |
Technical Analysis: All Optical Control of NV Centers in Single Crystal Diamond
Section titled âTechnical Analysis: All Optical Control of NV Centers in Single Crystal DiamondâThis documentation analyzes the requirements and findings of the research paper âAll optical control of a single electron spin in diamond,â focusing on material science specifications relevant to 6CCVDâs ultra-high purity MPCVD diamond products.
Executive Summary
Section titled âExecutive SummaryâThe research successfully demonstrated complete, all-optical coherent control of the Nitrogen-Vacancy (NVâ») center spin in diamond, eliminating the necessity for microwave addressing. This breakthrough hinges on the quality of the diamond material, offering significant opportunities for integrated quantum technologies.
- Core Achievement: Demonstrated all-optical initialization, fast coherent manipulation, and readout of the NVâ» electronic spin at T~7K.
- Methodology: Utilized high-purity Single Crystal Diamond (SCD) as a macroscopic Solid Immersion Lens (SIL) to maximize laser excitation and photon collection efficiency.
- Key Results: Achieved high spin polarization (> 80%) in the |-1â© state via optical pumping and observed two-photon Rabi oscillations in the ground state manifold.
- Material Necessity: The experiments require ultra-low strain, high-purity SCD substrates to maintain the long coherence times essential for quantum information processing.
- Applications: Opens pathways for robust manipulation of spin states using geometric quantum gates, quantum sensing, and scalable diamond-based nanophotonic networks where integrated microwave structures are impractical.
- 6CCVD Value: 6CCVD specializes in supplying the necessary low-strain, high-coherence Quantum Grade SCD wafers and customized optical components (like SILs) required to replicate and scale this research.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the research paper concerning the physical processes and material performance:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Operating Temperature | ~7 | K | Helium flow cryostat |
| Initialization Laser | 532 | nm | Spin and charge state initialization |
| Manipulation Lasers | 637 | nm | Resonant addressing of optical transitions |
| Optical Pumping Pulse Duration | 20 | ”s | Used for (0) â Eâ) transition |
| Selective Excitation Pulse Duration | 400 | ns | Used for |
| Spin Polarization Achieved | > 80 | % | Achieved in the |
| Zero Field Splitting (AZFS) | 2Ï x 2.88 | GHz | Ground state manifold |
| Two-Photon Detuning | 2 x 2.24 | GHz | Applied linearly polarized laser |
| Decay Rate (Spectral Diffusion) | 2Ï x 490 | MHz | Total decay rate of two-photon Rabi oscillations (Ύλ) |
| Applied Magnetic Field (B) | ~10 | G | Used only for initial characterization |
Key Methodologies
Section titled âKey MethodologiesâThe experiment successfully achieved all-optical control through precise temporal and spectral laser manipulation on a highly controlled diamond substrate:
- Sample Preparation: A macroscopic hemisphere of Single Crystal CVD Diamond (acting as a Solid Immersion Lens, SIL) was held at T~7K in a helium flow cryostat to enhance excitation efficiency and photon collection.
- Zeeman Splitting Generation: A permanent magnet was used to generate a small Zeeman splitting (B~10 G) of the |±1⩠states for initial system characterization.
- Spin Initialization (Optical Pumping): The NV center was initialized into the |-1â© state using a two-step process:
- A 532 nm laser pulse (20 ”s) pumped the spin states into |±1â©.
- A Ï polarized 637 nm laser selectively excited the |+1â© â |Aââ© transition (400 ns).
- Coherent Manipulation (Two-Photon Rabi): Two-photon Rabi oscillations between the |±1â© ground states were driven at zero magnetic field using a single linearly polarized laser detuned 2 x 2.24 GHz from the |±1â© â |Aââ© transition.
- Spin Readout: The population of the |±1â© state was measured directly by applying an optical pulse to the |Aââ© state and collecting emitted photons on the Phonon Sideband (PSB).
- Dark State Observation: Demonstrated coherent control across all three ground state spin levels by scanning a linearly polarized laser and modulating it via an EOM, resulting in the observation of double-dark resonances.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research validates the critical need for ultra-high-quality diamond materials for the development of integrated quantum optical systems. 6CCVD is uniquely positioned to supply the materials, customization, and engineering support necessary to scale these concepts into commercial or robust research prototypes.
Applicable Materials
Section titled âApplicable MaterialsâTo replicate and extend this research, the use of low-strain, high-purity Single Crystal Diamond (SCD) is mandatory. The material must minimize crystal defects and residual nitrogen concentration to ensure long NV coherence times (Tâ* and Tâ) necessary for effective Rabi oscillations.
| 6CCVD Material Solution | Description & Application Relevance |
|---|---|
| Quantum Grade SCD | Ultra-low-strain, high-pp purity SCD wafers (typical [N] < 1 ppb). Essential for minimizing spectral diffusion and achieving the coherence required for all-optical control and geometric gates. |
| Optical Grade SCD | Highly polished SCD plates (Ra < 1nm) suitable for solid immersion lenses (SILs) and on-chip nanophotonic devices, matching the high optical quality used in the paper. |
Customization Potential for Integrated Devices
Section titled âCustomization Potential for Integrated DevicesâThe paper highlights the incompatibility of traditional external microwave structures with scalable nanophotonic devices. 6CCVD provides the specialized material processing needed for on-chip integration, eliminating reliance on external bulk components.
- Custom Dimensions and Substrates: 6CCVD provides SCD plates up to 500 ”m thick, and customized substrates up to 10 mm. This capability supports the creation of macroscopic SILs as used in this paper, as well as thin membranes required for coupling to optical cavities and waveguides.
- Precision Polishing: Achieving efficient laser excitation and photon collection requires ultra-smooth surfaces. 6CCVD guarantees Ra < 1nm polishing on SCD, ensuring minimal light scattering loss at the diamond/air interface, critical for coupling to nanophotonic structures.
- Microfabrication Services: The development of integrated nanophotonic systems (as referenced in the paper [10-12]) requires precision structuring. 6CCVD offers high-resolution laser cutting and shaping services necessary to create custom-geometry components, such as high-NA SILs or integration with waveguides.
- Metalization Capability: While the all-optical method eliminates microwave structures, future hybrid quantum systems may require integrated electrodes or contacts. 6CCVD offers in-house metalization (Au, Pt, Pd, Ti, W, Cu) for engineers designing BDD- or electrically-tuned NV systems.
Engineering Support
Section titled âEngineering SupportâThe successful implementation of all-optical NV control relies on complex understanding of crystal strain, defect management, and surface chemistry. 6CCVDâs in-house PhD team provides expert consultation:
- Material Selection for Integrated Q-Nets: Our experts assist researchers in selecting the optimal SCD thickness and orientation for integrated nanophotonic devices, such as those leveraging optical cavities and waveguides for enhanced NV-light interactions.
- Strain Engineering: We collaborate on projects requiring ultra-low-strain diamond, which is essential for ensuring nearly degenerate dark states and robust coherent manipulation across the entire spin manifold, as demonstrated in this work.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Precise coherent control of the individual electronic spins associated with\natom-like impurities in the solid state is essential for applications in\nquantum information processing and quantum metrology. We demonstrate\nall-optical initialization, fast coherent manipulation, and readout of the\nelectronic spin of the negatively charged nitrogen-vacancy (NV$^-$) center in\ndiamond at T$\sim$7K. We then present the observation of a novel double-dark\nresonance in the spectroscopy of an individual NV center. These techniques open\nthe door for new applications ranging from robust manipulation of spin states\nusing geometric quantum gates to quantum sensing and information processing.\n