Reliable transfer of quantum information between nodes of quantum processors and memories is crucial for the realization of many groundbreaking technologies. These include distributed sensing, distributed computation, entanglement swapping, quantum metrology, quantum key distribution etc... which would vastly expand the potential of today’s quantum computers and form the framework for a secure quantum internet. However, most quantum nodes are accessed using visible photons which are incompatible with the telecom-band optical fiber network. In this thesis, we propose a method to bridge this spectral mismatch between the quantum nodes and the communication channel using a highly non-degenerate (810nm+1550nm) photon pair source using a Periodically Poled Potassium Titanyl Phosphate (PPKTP) crystal. Previous challenges with such frequency conversion systems like spectral filtering losses, out-coupling losses and feasibility of scalable fabrication are addressed by demonstrating the successful integration of the PPKTP crystal with a Silicon Photonics Integrated Circuit (Si-PIC). Higher pair detection rates than previous studies and efficient coupling between the crystal and the PIC chip are shown. Filter-free operation of the telecom band is demonstrated by using the Silicon waveguides on the PIC for pump photon absorption for the very first time.
Department, Program, or Center
School of Physics and Astronomy (COS)
Shunmuga Sundaram, Vijay Soorya, "Integration of a Visible-Telecom Photon Pair Source with Silicon Photonics for Quantum Communication" (2021). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus