Phonon Networks with Silicon-Vacancy Centers in Diamond Waveguides

We propose and analyze a novel realization of a solid-state quantum network, where separated silicon-vacancy centers are coupled via the phonon modes of a quasi-one-dimensional diamond waveguide. In our approach, quantum states encoded in long-lived electronic spin states can be converted into propagating phonon wave packets and be reabsorbed efficiently by a distant defect center. Our analysis shows that under realistic conditions, this approach enables the implementation of high-fidelity, scalable quantum communication protocols within chip-scale spin-qubit networks. Apart from quantum information processing, this setup constitutes a novel waveguide QED platform, where strong-coupling effects between solid-state defects and individual propagating phonons can be explored at the quantum level

Diamond optomechanical crystals

Cavity-optomechanical systems realized in single-crystal diamond are poised to benefit from its extraordinary material properties, including low mechanical dissipation and a wide optical transparency window. Diamond is also rich in optically active defects, such as the nitrogen-vacancy (NV) and silicon-vacancy (SiV) centers, which behave as atom-like systems in the solid state. Predictions and observations of coherent coupling of the NV electronic spin to phonons via lattice strain has motivated the development of diamond nanomechanical devices aimed at realization of hybrid quantum systems, in which phonons provide an interface with diamond spins. In this work, we demonstrate diamond optomechanical crystals (OMCs), a device platform to enable such applications, wherein the co-localization of ~ 200 THz photons and few to 10 GHz phonons in a quasi-periodic diamond nanostructure leads to coupling of an optical cavity field to a mechanical mode via radiation pressure. In contrast to other material systems, diamond OMCs operating in the resolved-sideband regime possess large intracavity photon capacity (> 10$^5$) and sufficient optomechanical coupling rates to reach a cooperativity of ~ 20 at room temperature, allowing for the observation of optomechanically induced transparency and the realization of large amplitude optomechanical self-oscillations

Strain engineering of the silicon-vacancy center in diamond

We control the electronic structure of the silicon-vacancy (SiV) color-center in diamond by changing its static strain environment with a nano-electro-mechanical system. This allows deterministic and local tuning of SiV optical and spin transition frequencies over a wide range, an essential step towards multi-qubit networks. In the process, we infer the strain Hamiltonian of the SiV revealing large strain susceptibilities of order 1 PHz/strain for the electronic orbital states. We identify regimes where the spin-orbit interaction results in a large strain suseptibility of order 100 THz/strain for spin transitions, and propose an experiment where the SiV spin is strongly coupled to a nanomechanical resonator

Strain engineering of the silicon-vacancy center in diamond

We control the electronic structure of the silicon-vacancy (SiV) color-center in diamond by changing its static strain environment with a nano-electro-mechanical system. This allows deterministic and local tuning of SiV optical and spin transition frequencies over a wide range, an essential step towards multiqubit networks. In the process, we infer the strain Hamiltonian of the SiV revealing large strain susceptibilities of order 1 PHz/strain for the electronic orbital states. We identify regimes where the spin-orbit interaction results in a large strain susceptibility of order 100 THz/strain for spin transitions, and propose an experiment where the SiV spin is strongly coupled to a nanomechanical resonator

A multicolor, broadband (5-20μm), quaternary-capped InAs/GaAs quantum dot infrared photodetector

Polarization-resolved resonant fluorescence of a single semiconductor quantum dot Appl. Phys. Lett. 101, 251118 (2012) Optical cavity efficacy and lasing of focused ion beam milled GaN/InGaN micropillars J. Appl. Phys. 112, 113516 (2012) Competitive carrier interactions influencing the emission dynamics of GaAsSb-capped InAs quantum dots Appl. Phys. Lett. 101, 231109 (2012) Fluorescence quantum efficiency of CdSe/ZnS quantum dots embedded in biofluids: pH dependenc

Effectiveness of modified carnoys compared to carnoys solution in preventing recurrence of odontogenic keratocysts: An original research

Introduction: Carnoy’s solution (CS), has been barred for 7 years, without data to support its effectiveness. Hence in the present study we evaluate the effectiveness of modified carnoys (MC) compared to carnoys solution in preventing recurrence of odontogenic keratocysts. Material and Methods:  We conducted a retrospective cohort study comparing CS or for the recurrence and time to recurrence. The values obtained were compared. Results: we observed that in both the recurrence was similar, Median time to recurrence was 2 years. Preserving adjacent teeth was associated with a significant increase in recurrence. Conclusion: We observed no significant difference in recurrence rate or distribution of time to recurrence between OKCs treated with CS or MC

Habermas, democracy and civil society: Unearthing the social in transformation theory

The debate as to whether transformative learning theory takes adequate account of the social has contributed to the clarification and development of the theory. But this debate has been, to a great extent, framed within transformation theory. This paper outlines some key ideas from Jürgen Habermas - civil society, public sphere, democracy and discourse - that are crucial to unearthing the social in transformation theory