ENG-QUANT: Entangled photon pair emission from quantum defects in 1D semiconductors

Optical photons are a key element for quantum communication because they are relatively free of decoherence and easy to manipulate and detect. Due to the ever-evolving quantum algorithms which require sophisticated gate operations, quantum light sources that can meet the many stringent requirements of these applications are needed. This project aims to develop a solid-state quantum photon source that is fully integratable with electronic and photonic devices and can generate high performance photon pairs on demand. This project will also provide training opportunities for our next-generation quantum workforce and promote the participation of underrepresented groups through a broad range of outreach programs. Optical qubits, where quantum information is encoded in the quantum states of photons using degrees of freedom such as polarization, are well suited for quantum information transfer and quantum metrology. This project will develop a new class of quantum emitters that can serve as polarization entangled photon pair sources. By controlling the atomic structures of the quantum emitters, their excitonic wavefunctions will be modified to support polarization entangled photon pair emission. To optimize the performance of the emitters, compact electro-photonic devices based on the host semiconductor will be assembled. The electrical modulation and Purcell effect afforded by the compact devices will allow emission optimization. This project will also shed light on fundamentals of quantum material design, as well as how environmental interactions affect optical coherence properties of quantum emitters. 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.