Optomechanical Quantum Control of a Nitrogen-Vacancy Center in Diamond
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2016-04-07 |
| Journal | Physical Review Letters |
| Authors | D. Andrew Golter, Thein Oo, Mayra Amezcua, Kevin A. Stewart, Hailin Wang |
| Institutions | Oregon State University, University of Oregon |
| Citations | 252 |
| Analysis | Full AI Review Included |
Diamond for Quantum Nanomechanics: Optomechanical Control of NV Centers
Section titled âDiamond for Quantum Nanomechanics: Optomechanical Control of NV Centersâ6CCVD Technical Analysis of âOptomechanical Quantum Control of a Nitrogen Vacancy Center in Diamondâ
This technical documentation analyzes the requirements and achievements of the demonstrated optomechanical quantum control of Nitrogen Vacancy (NV) centers in diamond. The research confirms diamond as the leading platform for hybrid quantum systems, leveraging its exceptional mechanical properties and established solid-state qubit functionality.
Executive Summary
Section titled âExecutive SummaryâThis paper demonstrates coherent quantum control over NV centers by simultaneously coupling them to optical fields and Surface Acoustic Waves (SAWs) in the resolved-sideband regime.
- Core Achievement: Successful realization of optomechanically-driven Rabi oscillations and quantum interference in a solid-state NV system.
- Resolved-Sideband Regime: Operation achieved where the mechanical frequency (~900 MHz) exceeds the decoherence rate for relevant optical transitions, enabling precise quantum control.
- Material Dependence: The successful realization hinges on the use of high-quality diamond substrates exhibiting exceptionally low mechanical loss and strain.
- NV Coupling Mechanism: Control is mediated by the strong excited-state electron-phonon coupling of the NV center, utilizing lattice strain induced by SAWs.
- Future Platform: This work establishes a major step toward developing a solid-state analog of trapped ions, potentially leading to scalable quantum information processing and sensing platforms.
- Material Requirements: Replication and extension of this research require high-purity Single Crystal Diamond (SCD) with superior surface finish for subsequent thin-film piezoelectric (ZnO) deposition and nanomechanical device (MEMS/SAW) fabrication.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points define the operational parameters and material specifications required for optomechanical quantum control experiments demonstrated in the study.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Sample Temperature | 8 | K | Operating temperature for quantum coherence |
| SAW Center Frequency (@m/2Ï) | 900 - 940 | MHz | Mechanical frequency of the surface acoustic wave |
| Piezoelectric Layer Material | ZnO | nm thick layer | Sputtered on diamond surface for IDT fabrication |
| Piezoelectric Layer Thickness | 400 | nm | Required thickness for SAW generation |
| NV Initialization Wavelength | 532 | nm | Off-resonant Green laser |
| Optomechanical Control Wavelength | 637 | nm | Optical transition used for coupling ( |
| Estimated Optical Rabi Frequency (Ω0/2ÏâP0) | 65 | MHz/â”W | Characterization of the incident laser power coupling |
| Low Power Linewidth | 175 | MHz | Linewidth limit primarily due to spectral diffusion |
| Estimated SAW Amplitude (ASAW) | 0.7 | pm | Minimal mechanical displacement required for Rabi oscillations |
| Estimated Single-Phonon Coupling Rate | Order 2 | MHz | For a 1 pg, 900 MHz nanomechanical oscillator |
Key Methodologies
Section titled âKey MethodologiesâThe experimental success relied on combining high-quality material selection with precision nanophotonics and SAW engineering.
- Substrate Preparation: Utilization of a high-quality diamond substrate to minimize mechanical loss and spectral diffusion effects.
- Piezoelectric Film Deposition: A 400 nm thick layer of strongly piezoelectric Zinc Oxide (ZnO) was sputtered onto the diamond surface.
- SAW Transducer Fabrication: Inter-Digital Transducers (IDTs) were patterned onto the ZnO layer using high-resolution Electron Beam Lithography (EBL).
- NV Center Preparation: A single NV center, situated a few ”m below the diamond surface, was initialized into the ms=0 ground state using an off-resonant green laser (532 nm).
- Simultaneous Driving: The NV center was driven simultaneously by the propagating SAW field and a continuous-wave (CW) optical field tuned to the red sideband resonance (near 637 nm).
- Coherent Control: Rabi oscillations were driven by controlling the acoustic pulse duration (90 ns increments) and confirmed via normalized fluorescence measurements.
- Quantum Interference: Coherent interference between the direct dipole-optical transition and the optomechanical sideband transition was observed by tuning the relative phase and frequency of the optical fields via an Acousto-Optic Modulator (AOM).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & Capabilitiesâ6CCVD provides the necessary material foundation and engineering services required to replicate and advance high-fidelity quantum optomechanical systems. Our capabilities directly address the strict material purity, structural integrity, and custom processing demands of NV-based nanomechanics.
Applicable Materials
Section titled âApplicable MaterialsâThe foundation of high-coherence NV quantum systems lies in ultra-pure, low-strain diamond.
- Recommended Material: High-Purity Electronic Grade Single Crystal Diamond (SCD).
- Purity: Essential for minimizing spectral diffusion and achieving the ultra-long spin decoherence times necessary for high-fidelity quantum control (Ref. 41).
- Mechanical Loss: SCD offers exceptionally low mechanical loss (Ref. 26), crucial for high-Q diamond nanomechanical resonators required for motional state control.
- Substrate Dimension: We offer SCD wafers suitable for MEMS processing, providing custom dimensions and thicknesses up to 500 ”m, allowing ample margin for deep processing or specific NV implantation depths (few ”m required in this study).
Customization Potential
Section titled âCustomization PotentialâThe utilization of IDTs and piezoelectric films requires a superior starting surface quality, which 6CCVD guarantees through industry-leading polishing standards.
| Service | 6CCVD Capability | Relevance to Optomechanics Research |
|---|---|---|
| Surface Finish (Polishing) | SCD: Ra < 1nm (Optical Grade) | Necessary for high-quality sputtering/deposition of the 400 nm ZnO layer and subsequent EBL patterning of IDTs/nanomechanical structures. |
| Custom Dimensions | Plates/Wafers up to 125mm (PCD) / Standard SCD | Supplies large-format substrates for advanced foundry-style MEMS and SAW fabrication runs. |
| Custom Metalization | Au, Pt, Pd, Ti, W, Cu (Internal capability) | While the IDTs were ZnO-patterned, 6CCVD can integrate contact pads and high-frequency interconnects critical for RF signal application (PRF up to 0.45 W) to the transducers. |
| Substrate Thickness | SCD (0.1”m - 500”m), Substrates (up to 10mm) | Enables the use of thinner membranes for flexible nanomechanical resonator designs or robust bulk diamond platforms for SAW transmission. |
Engineering Support
Section titled âEngineering SupportâDeveloping hybrid NV-nanomechanical systems is highly specialized. 6CCVDâs in-house team of PhD material scientists and engineers are available to support complex research requirements.
- Application Focus: We specialize in material selection and specification optimization for hybrid quantum systems, including strain-mediated coupling and high-Q resonator designs.
- Technical Consultation: Assistance with defining substrate orientation, minimizing crystal strain, and optimizing polishing processes to facilitate uniform thin-film growth and NV initialization procedures.
- Global Logistics: We ensure reliable, secure, global delivery (DDU default, DDP available) of sensitive, high-value diamond materials directly to your research laboratory or fabrication facility.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
We demonstrate optomechanical quantum control of the internal electronic states of a diamond nitrogen-vacancy (NV) center in the resolved-sideband regime by coupling the NV to both optical fields and surface acoustic waves via a phonon-assisted optical transition and by taking advantage of the strong excited-state electron-phonon coupling of a NV center. Optomechanically driven Rabi oscillations as well as quantum interferences between the optomechanical sideband and the direct dipole-optical transitions are realized. These studies open the door to using resolved-sideband optomechanical coupling for quantum control of both the atomlike internal states and the motional states of a coupled NV-nanomechanical system, leading to the development of a solid-state analog of trapped ions.