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The induced transparency of opaque medium for resonant electromagnetic radiation is a powerful tool for manipulating the field-matter interaction. Various techniques to make different physical systems transparent for radiation from microwaves to x-rays were implemented. Most of them are based on the modification of the quantum-optical properties of the medium under the action of an external coherent electromagnetic field. Recently, an observation of acoustically induced transparency (AIT) of the⁵⁷Fe absorber for resonant 14.4-keV photons from the radioactive⁵⁷Co source was reported. About 150-fold suppression of the resonant absorption of photons due to collective acoustic oscillations of the nuclei was demonstrated. In this paper, we extend the AIT phenomenon to a novel phase-locked regime, when the transmitted photons are synchronized with the absorber vibration. We show that the advantages of synchrotron Mössbauer sources such as the deterministic periodic emission of radiation and controlled spectral-temporal characteristics of the emitted photons along with high-intensity photon flux in a tightly focused beam, make it possible to efficiently implement this regime, paving the way for the development of the acoustically controlled interface between hard x-ray photons and nuclear ensembles.

 

We present the design, fabrication and characterization of high quality factor silicon nitride nanobeam PhC cavities at visible wavelengths for coupling to diamond color centers in a cavity QED system. We demonstrate devices with a quality factor of ∼24, 000 (±250) around the zero-phonon line of the germanium-vacancy center in diamond. We also present an efficient fiber-to-waveguide coupling platform for suspended nanophotonics. By gently changing the corresponding effective indices at the fiber-waveguide interface, we achieve a coupling efficiency of ∼96% (±2%) at the cavity resonance.

 

Development of quantum information processing requires realization of solid state structures able to manipulate light or matter quantum bits. One of the promising candidates for been active elements of such solid-state platform are color centers in diamond. The most famous nitrogen-vacancy color center has number of attractive features and found a lot of applications in sensing and imaging. Still, it has number of considerable disadvantages, among which it sensitivity to the surface damages and thus its incompatibility with nanostructures. On another side implementation of nano- and micro- structures enabled considerable progress in manipulation of light quanta. In particular photonic crystal cavities allowed to realize strong coupling of cavity and spin system. This led to demonstration of efficient light collection and realization of simple quantum gates with artificial or real atoms. Novel color centers such as silicon-vacancy or germanium-vacancy color center due to inversion symmetry of the electron structure are not sensitive to the surface damages and presence of surface nearby. Thus, those are perfect candidates for been combined with photonic crystal structures. Novel technologies enabled growing of the nanodiamonds of ultra-small size having well-defined color center inside. Along with techniques to position those precisely on the nano- and micro structures these achievements opened opportunity to integrate high-fines photonic-crystal cavities with the germanium-vacancy containing nanocrystals thus forming fully solid-state platform for quantum manipulation of light. In my talk I will describe our progress towards realization of this ambitious goal