Toward wafer-scale diamond nano- and quantum technologies

Abstract

We investigate native nitrogen (NV) and silicon vacancy (SiV) color centers in commercially available, heteroepitaxial, wafer-sized, mm thick, single-crystal diamond. We observe single, native NV centers with a density of roughly 1 NV per µm 3 and moderate coherence time (T 2 = 5 µs) embedded in an ensemble of SiV centers. Low-temperature spectroscopy of the SiV zero phonon line fine structure witnesses high crystalline quality of the diamond especially close to the growth surface, consistent with a reduced dislocation density. Using ion implantation and plasma etching, we verify the possibility to fabricate nanostructures with shallow color centers rendering our diamond material promising for fabrication of nanoscale sensing devices. As this diamond is available in wafer-sizes up to 100 mm it offers the opportunity to up-scale diamond-based device fabrication. PACS numbers: Valid PACS appear hereDiamond nanostructures are of significant importance for various applications in science and industry including nanomechanical devices, 1 photonics 2 and sensing. 3 A major challenge for most of these applications is the scalability of the fabrication process predominantly due to a lack of large area single-crystal diamonds with good crystalline quality and high purity. Manufacturing synthetic, single-crystal diamond on wafer-scale has been an active field of research 4,5 leading to the commercial availability of single-crystal diamonds with a diameter of ≈ 100 mm recently. This progress opens the road towards up-scaling the fabrication of single-crystal nanostructures especially for diamond related sensing applications. 6 Color centers in diamond, in particular the negatively-charged nitrogen vacancy (NV) center in nanostructures, have been extensively used to sensitively measure e.g. magnetic fields in the last decade. Recently, silicon vacancy (SiV) centers emerged as alternative enabling all optical sensing of temperatures using their narrow electronic transitions. 7 Single color centers allow for sensing with high spatial resolution and offer bright, photostable photoluminescence (PL). In addition, NV centers provide highly-coherent, controllable spin states 3 and show optically-detected magnetic resonance (ODMR) enabling to read out their spin states via PL detection. As a consequence, even single NV centers can serve as quantum-enhanced sensors. Magnetic field imaging using NV centers has various applications ranging from material characterization in superconductors 8 or magnetic materials for spintronics 9 to life science applications where nuclear magnetic resonance detection of single proteins is of interest. 10 We here demonstrate the basic applicability of commercial, single-crystal, wafer-sized diamonds for quantum a) Electronic mail: elkeneu@physik.uni-saarland.de technology applications. To this end, we demonstrate coherent manipulation of single native NV center spins in the material, while low-temperature spectroscopy of SiV center PL indicates high crystalline quality of the material. In addition, we im...

Near‐Field Energy Transfer between a Luminescent 2D Material and Color Centers in Diamond

“…In contrast, in areas not covered by WSe 2 flakes we consistently measure a much longer NV lifetime with an average value of 12(1) ns (see Figure c), typical for NV centers in bulk diamond . For shallowly implanted NVs, slightly longer lifetimes of ≈ 16–17 ns have been previously reported . We point out that, in our experiment, residuals from the transfer process might slightly reduce the NV lifetime in between the flakes.…”

Microstrip-line resonator with broadband, circularly polarized, uniform microwave field for nitrogen vacancy center ensembles in diamond

“…The negatively charged nitrogen-vacancy (NV -) center in diamond consisting of a substitutional nitrogen atom together with an adjacent vacancy 1 are widely used in quantum information 2,3 and sensing. 4,5 The NVcenter ensemble is promising for magnetic measuring and temperature measuring devices 6,7 according to its extraordinary properties, such as long spin coherence time, 8 visible initialization and read-out 9 and microwave (MW) manipulation. 10,11 State manipulation 12 of the NVcenter ensembles through the MW field 13,14 provides strong technical support for measurement of the magnetic field.…”

Plasma treatments and photonic nanostructures for shallow nitrogen vacancy centers in diamond

“…Both ensembles show similar average τ NV − 17(1) ns in area I and 16(1) ns in area III. τ NV − is thus prolonged compared to bulk SCD due to the NV − 's proximity to the surface[36]. In addition, the measurements clearly show an absence of quenching.…”

“…We obtain comparable results for both areas with τ NV − =17(1) ns for area I and τ NV − =16(1) ns for area III, respectively. Here, τ NV − is longer than the bulk lifetime (12 ns) due to the NV − 's proximity to the surface [36]. However, we exclude quenching which would reduce τ NV − .…”