EAGER: Ion-implanted atom-like defects in semiconductors for single-photon emission at telecommunication wavelengths

Nontechnical Description: Artificial light with special properties plays a critical role in a number of technologies. Modern communication systems, for example, benefit from the special properties of laser light, which permit low-loss, high-bandwidth, long-distance transmission of information. Ordinary illumination benefits from use of light-emitting diodes in lamps that are brighter and more efficient. This project investigates yet another quest for special properties of light sources: single photon emission. It will investigate deliberately engineered defects in wide bandgap semiconductors; specifically, how to create them so that they behave as isolated single atoms capable of emitting single particles of light at certain chosen wavelengths. Such structures are useful for design of future single-photon emitters. The discrete or particulate nature of light endows it with unique quantum properties that make it useful as a building block for construction of certain classes of quantum computing devices, and for developing special cryptographic hardware for future ultra-secure communication and computing networks. In addition to contributing new knowledge, the project will serve as a training vehicle for a new generation of highly interdisciplinary engineers in quantum information science and technology. Technical Description: This effort proposes deterministic creation of atom-like defects in SiC and Al_x Ga_(1-x) N semiconductor films by focused-ion beam implantation at lithographically defined spatial locations. The objective is to implant elements such as vanadium, erbium, and others to form optically active defects that emit at the two low-loss telecommunication wavelengths of 1.3 and1.55 microns. Following post-implantation annealing, the samples will be characterized by rocking curve x-ray diffraction to assess crystallinity. Additional characterization will include spatially resolved micro-photoluminescence. Evidence for quantum light production will be derived from second-order autocorrelation of light emitted by the photoexcited defects. Preliminary feasibility experiments for electrical excitation in specially designed structures with defects in them will also be performed. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.