Single Photon Emission Enhancement by Deterministic Bottom Up Manufacturing of Plasmonic nanoStructures

Quantum information represents a paradigm-shift in the way we exchange information, with the EU and the US investing substantial economic resources on basic research and technological developments. Propelled by these efforts, the research community intensely worked on physical sources of quantum bits, qubits, the quantum information basic units. In particular, Single Photon Sources (SPS) offer the perspective of modular quantum information circuitry elements. In this framework, transition from fundamental research to technology is a necessary step towards their use in a broader and application-oriented use.SPEEDBUMPS will develop plasmonic-enhanced tapered optical nanofibers (ONF), a highly reliable SPS generation and collection system exploiting on-waveguide localized plasmon surface resonances to generate periodic flows of single photons on a ready-for-integration waveguide with enhanced optical properties.To do this it will pursue three main objectives to surpass the current state-of-art of fiber-based SPS: 1. Exploiting SPS typically requires bulky optical setups, limiting the translation in applicative frameworks where no strong expertise in optical systems is required. SPEEDBUMPS will demonstrate the integration of SPS with other optical systems, coupling them with the strong evanescent field confined at the surface of a ONF.2. SPS-ONF coupling alone fails at obtaining collection efficiencies higher than the 10% of the photons emitted by the SPS. To increase the system efficiency SPEEDBUMPS will realize an optical cavity deterministically fabricated on the ONF with unconventional nanofabrication approaches.3. To further increase the efficiency, in SPEEDBUMPS the isotropic radiation field will be modified through complex nanostructuring of the ONF to realize field-redirecting elements.Due to the ONFs nature (suspended, dielectric, curved, nanometric) these results will be unprecedented, paving the way to novel applications in the field of quantum optics.