Enabling QUAntum Information by Scalability of Engineered quantum materials

EQUAISE is a QUANTERA project funded in 2021. The project is going to start in June 2022. Stay tuned!

Future quantum applications require non-classical light sources that emit indistinguishable photons on-demand with high efficiency and purity. A stringent requirement for industrial applications is that these sources are fabricated via simple and cost-effective methods and, at the same time, be compatible with current photonic integration technologies. The performance of solid-state quantum emitters and single photon sources has been significantly improved, owing to almost 20 years of extensive engineering efforts. However, bringing them out of research laboratories remains a grand challenge, mainly due to the difficulty of fulfilling the scalability requirement set by quantum technologies. Here, we propose a novel approach to fabricate arrays of near-ideal single-photon sources. The sources will be realized starting from two-dimensional materials made of transition metal dichalcogenides (TMDs). Atomically thin TMDs can be easily produced, are cost-effective and, thanks to their inherently flexible nature, their optical properties can be seamlessly tuned. Furthermore, the emission from these materials may cover the wavelength region of interest for signal transmission through optical fibers. We will combine mechanics and electrochemistry to deform and shape two-dimensional membranes made of TMDs at the nanoscale and transform them into site-controlled single photon sources. The fabrication of our source arrays in TMD membranes will be accomplished following two complementary procedures: i) mechanical nano-indentation and ii) hydrogen-assisted formation of nanobubbles. In both instances, the sources will be created spatially and spectrally resonant with the electromagnetic field of a circular Bragg-grating microcavity to ensure efficient light extraction and single-mode fiber coupling. These hybrid structures will be integrated onto micro-machined piezoelectric devices for controlling their emission properties independently by strain engineering. A single chip hosting several non-classical light sources will be fabricated in scalable manner with each source being independently addressable by external bias. This will permit to perform photon processing involving two or more quantum emitters integrated in a single compact device reducing the operating costs dramatically and enhancing the opportunities to test complex arrangements within quantum communications and simulation.