#### QES Seminar, 4/12/10: Entangled Photonic Qubits in the Spatial-Parity Space

(More about event)Prof. Bahaa Saleh

CREOL, The College of Optics and Photonics

University of Central Florida

ABSTRACT

We have developed a novel embodiment of a photonic qubit based on the parity of a single photon's transverse spatial distribution in one dimension. We identify and construct experimental arrangements comprising simple linear optical components that implement Pauli spin operators, as well as rotation, in the spatial parity space. An interferometric device, isomorphic in action to a polarizing beam splitter, was used to project the spatial-parity states onto an even-odd basis. Using spontaneous parametric downconversion (SPDC) to produce photon pairs, we experimentally demonstrated the controlled generation of entangled-photon states in this new space. Specifically, two Bell states and their superpositions were generated by the simple manipulation of a classical parameter, the optical-pump spatial parity, and not by manipulation of the entangled photons themselves. This new physical realization of photonic qubits is used to demonstrate parity interferometry. Violation of BellÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂs inequality was demonstrated in this ÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂbinarizedÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ? continuous-spatial-variable regime. Many applications in quantum information processing are envisioned. While each photon carries one polarization qubit, it has two transverse dimensions so that one qubit can be encoded in each. Furthermore, these two spatial-parity qubits per photon may be led to interact using simple optical arrangements. The two-photon SPDC state thus carries four parity qubits.

BIO

Bahaa Saleh has been Dean of CREOL, The College of Optics and Photonics, at the University of Central Florida, since January 2009. He was Chair of the ECE Department at Boston University (1994-2007) and Chair of ECE at the University of Wisconsin-Madison (1990 to 1994). His research contributions cover a broad spectrum of topics in optics and photonics including statistical optics, nonlinear and quantum optics, and image science. He author of Photoelectron Statistics (Springer, 1978) and co-author of Fundamentals of Photonics (with M. Teich, Wiley, 1991, 2007) and more than 500 papers in technical journals and conference proceedings. He is the founding editor of OSAÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂs Advances in Optics and Photonics and a previous editor of the Journal of Optical Society of America A. His awards include: OSA Beller Award (1999), SPIE BACUS award (2004), Kuwait Prize (2006), and OSA Distinguished Service Award (2008). He is Fellow of IEEE, OSA, SPIE, and the Guggenheim Foundation.

**Location:**
Bowen Hall Atrium

**Date/Time: **04/12/10
at
12:30 pm
- 04/12/10
at
01:30 am

PIZZA AT NOON: SEMINAR AT 12:30 PM

This seminar series expands upon the highly successful lunch-time Quantum Computation series co-sponsored by PCTS and MITRE. The series emphasizes the engineering of quantum systems and ways in which quantum entanglement and concepts from quantum information science and engineering can be used for higher sensitivity and resolution sensing.

Co-sponsored by PRISM and the MITRE corporation.

Organizers: Rob Calderbank, Gerry Gilbert (MITRE), Andrew Houck, Steve Lyon, Yaakov Weinstein (MITRE).

Day: Mondays

Time: Pizza at noon, seminar starts at 12:30pm

Place: Bowen Hall Auditorium (lunch in atrium)

**Category: **PRISM/MITRE (QES) Seminar Series

**Department: **PRISM