Collaborative Research: Integrated Optics Using Quantum State Control in Alkali Atoms

University Of California-Santa Cruz, Santa Cruz CA

Investigators

Abstract

0500602 Schmidt Recent work in quantum interference in alkali vapors has shown some spectacular and well-publicized results. This type of atomic quantum state control can be used to reduce the speed of light down to a few meters per second, temporarily store the quantum state of a photon in an atomic medium, render an opaque medium transparent, and realize phase modulation and optical switching with few or single photons. Intellectual Merit: In order to move quantum interference from fundamental physics towards practical device applications, alkali vapors need to be integrated into optical waveguides on a semiconductor chip. To do so, an optical waveguide is required where light is guided in the low-index vapor. This has never been realized in atomic vapor, but can be achieved in antiresonant reflecting optical (ARROW) waveguides. Here, optical quantum interference is combined with design and fabrication of ARROW waveguides to develop an integrated platform for the use of quantum interference in alkali atoms for integrated optical devices in linear and nonlinear optics. The research is based on an existing strong collaboration between researchers at UC Santa Cruz and Brigham Young University and covers the following areas: Fabrication of alkali vapor containing hollow-core ARROW waveguides on a silicon chip, evaluation of the coherence as a function of waveguide dimensions, demonstration of linear and nonlinear quantum interference effects, and integrated optical devices relying on quantum state control on a chip. In particular, proof-of principle demonstration of a nonlinear optical switch operating at the few-photon level will be pursued. Broader Impact: In addition to contributing to the fields of integrated optics and quantum optics, the work contains a strong educational component taking advantage of the collaboration between UC Santa Cruz and Brigham Young University. Graduate student training in integrated optics, quantum optics, and device fabrication will be enhanced by extended visits to the partner university to receive training in the complementary research areas. At UC Santa Cruz, two undergraduate students from underrepresented and underprivileged groups will participate in the project for one year under the UC LEADS program. These students will also spend time at BYU to learn semiconductor fabrication techniques. At BYU, several undergraduates will be involved in the fabrication aspects of the projects under the BYU Microfabrication Mentoring Environment program. In addition, outreach visits to community and regional colleges such as Utah Valley State College will be arranged to help encourage students to pursue further education.