Local excitation of surface plasmon polaritons using nitrogen-vacancy centers
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2015-08-06 |
| Journal | Optics Letters |
| Authors | Cesar E. GarciaâOrtiz, Shailesh Kumar, Sergey I. Bozhevolnyi, Cesar E. GarciaâOrtiz, Shailesh Kumar |
| Institutions | University of Southern Denmark, Center for Scientific Research and Higher Education at Ensenada |
| Citations | 4 |
| Analysis | Full AI Review Included |
Technical Analysis and Commercial Opportunity Assessment: NV Center SPP Excitation
Section titled âTechnical Analysis and Commercial Opportunity Assessment: NV Center SPP ExcitationâExecutive Summary
Section titled âExecutive SummaryâThis research demonstrates the highly efficient local excitation and propagation of Surface Plasmon Polaritons (SPPs) using sub-wavelength Nanodiamonds (NDs) containing multiple Nitrogen-Vacancy (NV) centers. This technique is critical for developing next-generation integrated plasmonic devices, quantum optical systems, and novel sensing technologies.
- Core Achievement: NDs (~100 nm diameter) containing high densities of NV centers (~400) function effectively as stable, sub-wavelength optical sources for generating propagating SPPs on a silver/SiO2 interface.
- Efficiency: The experiment confirmed strong SPP-mediated light scattering, achieving a high extinction ratio (HH:VV = 26 or 14 dB), validating the classical coupling efficiency of the NV fluorescence into the SPP mode.
- Stability & Scalability: The photostability and high intensity fluorescence of multiple NV centers make these materials ideal for systematic use in integrated plasmonics requiring reliable and stable SPP sources.
- Material Quality Dependence: The observed short-wavelength filtering is directly linked to ohmic losses in the metal, emphasizing the necessity of ultra-high-quality, ultra-flat diamond-based components for minimal optical loss and maximum SPP propagation distance.
- 6CCVD Value Proposition: 6CCVDâs expertise in large-area, high-purity Single Crystal Diamond (SCD) wafers and custom metalization/polishing is ideally suited to transition this proof-of-concept research into robust, scalable planar integrated plasmonic devices.
Technical Specifications
Section titled âTechnical SpecificationsâThe following parameters and performance metrics were extracted from the experimental configuration and results:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Nanodiamond (ND) Diameter | ~100 | nm | Size of ND source (ND1) and scatterer (ND2) |
| NV Center Concentration | ~400 | Centers | Estimated per nanodiamond particle |
| Substrate Silver Thickness | 70 | nm | SPP supporting metallic layer |
| Dielectric Protective Layer | 15 | nm | SiO2 coating above silver film |
| ND Separation Distance ($d$) | 24 | ”m | Distance between ND1 (Source) and ND2 (Scatterer) |
| Excitation Wavelength (Pump) | 532 | nm | Frequency doubled Nd:YAG laser |
| Estimated SPP Propagation Length (λ=532 nm) | ~5 | ”m | Estimate for propagation limit at pump wavelength |
| NV- Zero-Phonon Line (ZPL) | 637 | nm | Key quantum emission line |
| Maximum Extinction Ratio (HH:VV) | 26 (14 dB) | Ratio (dB) | Demonstrating polarization-dependent SPP coupling |
| System Efficiency Factor ($f$) | 0.12 | Dimensionless | Fitted parameter for NV-SPP coupling efficiency |
| Calculation Fit Accuracy ($R^{2}$) | 0.96 | Dimensionless | Good correlation above the 637 nm ZPL |
Key Methodologies
Section titled âKey MethodologiesâThe experiment utilized thin-film deposition and high-resolution lithography techniques to precisely control the environment and placement of the diamond sources.
- Substrate Fabrication: A silver thin film (70 nm) was deposited to support SPPs, followed by a 15 nm thick SiO2 protective coating layer to prevent oxidation and sulfur reaction.
- ND Patterning and Placement:
- A PMMA (Polymethyl methacrylate) resist was patterned using e-beam lithography.
- A subsequent liftoff process was performed to ensure individual NDs were positioned precisely at controlled distances (24 ”m separation for the main experiment) and prevent uncontrolled clustering.
- Optical Excitation: The local source (ND1) was pumped using a 532 nm Nd:YAG laser focused by a 100x objective to a 1 ”m spot on the sample surface, through an inverted microscope setup.
- Signal Collection and Filtering: Fluorescence and scattered light were collected by the same objective. A longpass filter (550 nm) was used to block the pump beam.
- Polarization Analysis: An analyzer was used to filter field components into horizontal (H) and vertical (V) polarizations (HH, HV, VH, VV configurations) to confirm that scattering was mediated by SPPs propagating in the H-direction.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & Capabilitiesâ6CCVD is uniquely positioned to supply the advanced diamond materials and customization services required to replicate, scale, and optimize this foundational research for commercial integrated plasmonics and quantum optics applications.
Applicable Materials
Section titled âApplicable MaterialsâWhile the paper utilized ~100 nm nanodiamonds, optimizing performance requires planar, low-loss interfaces achievable with high-quality MPCVD films.
| Requirement | 6CCVD Material Solution | Rationale and Value Proposition |
|---|---|---|
| Integrated Plasmonics Substrate | Optical Grade Single Crystal Diamond (SCD) | Provides the lowest possible background fluorescence and superior thermal management. High-purity SCD offers the best platform for subsequent NV creation (via implantation or in-situ growth) with nanoscale positional control, crucial for optimizing SPP coupling. |
| High-Density NV Platforms | SCD or Polycrystalline Diamond (PCD) Wafers | We offer SCD (0.1 ”m - 500 ”m) and PCD (0.1 ”m - 500 ”m) films up to 125 mm diameter. This scale enables the fabrication of complex, high-volume planar devices such as plasmonic waveguides (V-grooves, dielectric-loaded waveguides) referenced in the paper. |
| Low-Loss Interface | Polished SCD Plates (Ra < 1 nm) | Minimizing surface roughness is critical. SPP scattering losses are highly dependent on surface quality. Our sub-nanometer polishing capability ensures the required optical flatness for maximum SPP propagation length, exceeding the estimated 5 ”m cited in the research. |
Customization Potential
Section titled âCustomization PotentialâThe experimental fabrication relied heavily on precise patterning and multi-layer deposition, services 6CCVD provides in-house for seamless device integration.
- Custom Dimensions and Shapes: 6CCVD offers laser cutting services to achieve the specific micron-scale component sizes necessary for integrated devices, including complex shapes for nano-antennas and V-grooves.
- Thin Film Stacks and Metalization: The experiment utilized a Ag/SiO2 stack. 6CCVD offers comprehensive internal metalization capabilities, including deposition of Au, Pt, Pd, Ti, W, and Cu. We can collaborate to deposit SPP-supporting films (e.g., Ag or Au) directly onto custom diamond substrates, facilitating clean, high-adhesion interfaces.
- Controlled NV Doping: For researchers focusing on quantum properties, 6CCVD can assist in providing SCD materials pre-optimized for specific NV concentration via in-house doping or subsequent implantation recipes.
Engineering Support
Section titled âEngineering SupportâThis research successfully characterized NV-SPP coupling via a classical approximation. Transitioning this work to quantum applications (e.g., single NV photon sources) requires specialized material engineering.
6CCVDâs in-house PhD material science team specializes in optimizing diamond crystal growth recipes to match demanding application requirements. We offer consultation on:
- Material selection for similar integrated plasmonic waveguide and quantum sensing projects.
- Balancing defect density (NV concentration) against spectral homogeneity and coherence time.
- Designing diamond/metal/dielectric stacks to maximize coupling efficiency ($\eta_{spp}$) and minimize surface scattering losses.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. Global shipping is standard (DDU default, DDP available).
View Original Abstract
Surface plasmon polaritons (SPPs) are locally excited at silver surfaces using (âŒ100) nanometer-sized nanodiamonds (NDs) with multiple nitrogen-vacancy (NV) centers (âŒ400). The fluorescences from an externally illuminated (at 532 nm) ND and from nearby NDs, which are not illuminated but produce out-of-plane scattering of SPPs excited by the illuminated ND, exhibit distinctly different wavelength spectra, showing short-wavelength filtering due to the SPP propagation loss. The results indicate that NDs with multiple NV centers can be used as efficient subwavelength SPP sources in planar integrated plasmonics for various applications.