Lachlan J. Rogers

Excited-state spectroscopy of single NV defects in diamond using optically detected magnetic resonance.

Using pulsed optically detected magnetic resonance techniques, we directly probe electron-spin resonance transitions in the excited-state of single nitrogen-vacancy (NV) color centers in diamond. Unambiguous assignment of excited state fine structure is made, based on changes of NV defect photoluminescence lifetime. This study provides significant insight into the structure of the emitting 3 E excited state, which is invaluable for the development of diamond-based quantum information processing.

Low temperature studies of the excited-state structure of negatively charged nitrogen-vacancy color centers in diamond.

We report a study of the 3E excited-state structure of single negatively charged nitrogen-vacancy (NV) defects in diamond, combining resonant excitation at cryogenic temperatures and optically detected magnetic resonance. A theoretical model is developed and shows excellent agreement with experimental observations. In addition, we show that the two orbital branches associated with the 3E excited state are averaged when operating at room temperature. This study leads to an improved physical understanding of the NV defect electronic structure, which is invaluable for the development of diamond-based quantum information processing.

Multiple intrinsically identical single-photon emitters in the solid state

Emitters of indistinguishable single photons are crucial for the growing field of quantum technologies. To realize scalability and increase the complexity of quantum optics technologies, multiple independent yet identical single-photon emitters are required. However, typical solid-state single-photon sources are inherently dissimilar, necessitating the use of electrical feedback or optical cavities to improve spectral overlap between distinct emitters. Here we demonstrate bright silicon vacancy (SiV(-)) centres in low-strain bulk diamond, which show spectral overlap of up to 91% and nearly transform-limited excitation linewidths. This is the first time that distinct single-photon emitters in the solid state have shown intrinsically identical spectral properties. Our results have impact on the application of single-photon sources for quantum optics and cryptography.

Infrared emission of the NV centre in diamond: Zeeman and uniaxial stress studies

An emission band in the infrared (IR) is shown to be associated with a transition within the negative nitrogen-vacancy centre in diamond. The band has a zero-phonon line at 1046?nm, and uniaxial stress and magnetic field measurements indicate that the emission is associated with a transition between 1E and 1A1 singlet levels. Inter-system crossing to these singlets causes the spin polarization that makes the NV- centre attractive for quantum information processing, and the IR emission band provides a new avenue for using the centre in such applications.

Electronic structure of the negatively charged silicon-vacancy center in diamond

The negatively-charged silicon-vacancy (SiV

Spectroscopy of surface-induced noise using shallow spins in diamond

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All-Optical Initialization, Readout, and Coherent Preparation of Single Silicon-Vacancy Spins in Diamond

) center in diamond is a promising single photon source for quantum communications and information processing. However, the centers implementation in such quantum technologies is hindered by contention surrounding its fundamental properties. Here we present optical polarization measurements of single centers in bulk diamond that resolve this state of contention and establish that the center has a

Germanium-Vacancy Single Color Centers in Diamond

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Time-averaging within the excited state of the nitrogen-vacancy centre in diamond

aligned split-vacancy structure with

Quantum nonlinear optics with a germanium-vacancy color center in a nanoscale diamond waveguide

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