RUI: Free Space Multimode Quantum Optics

Pacific University, Forest Grove OR

Investigators

Abstract

Free-space optical communication systems are a leading candidate for global quantum-key distribution networks. Recent results have demonstrated the feasibility of networks that include key distribution and secure quantum information transfer via ground-to-satellite channels. These optical channels, however, suffer from disruptive atmospheric effects due to airborne water vapor, smoke particles, and turbulence. The goal of this program is to apply multimode quantum state measurement techniques to free-space optical systems. Building on an existing research program, this project will create opportunities for students to study quantum optics at the cutting edge of the field while working on an accessible system with immediate applications to technological advancements. Undergraduate researchers participate in every step of the project, and gain experience with experiment design, data collection, analysis, and dissemination. The technical skills acquired during this experience, combined with attentive mentoring in a supportive research community, prepare students for successful science careers. Attendance and presentations at regional and national conferences provide students with insight into the scientific profession and an opportunity to expand their network of peers. Additionally, students will participate in a regional four-school consortium of atomic, molecular, and optical physics research groups. This program applies a new quantum state measurement technique to experimental systems that distribute quantum states via free-space channels. The result is a more complete understanding of the quantum state of light before and after atmospheric transmission. Array detection methods maximize the retrieved photon number and allow computation of the retrieved spatial mode. Compared to single-mode detection schemes, these methods recover more information on the quantum state of light. Array detection is also used to compare multiple retrieved modes, and reveal correlations between modes. This information reveals fundamental properties of the optical channel and will lead to channel optimization. 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.