October 24, 2003

Colloquium Topic: Quantum Computing Using Linear Optics

Quantum computers are expected to be able to solve mathematical problems that cannot be solved using conventional computers. Many of these problems are of practical importance, especially in the areas of cryptography and secure communications. APL is developing an optical approach to quantum computing in which the bits, or "qubits", are represented by single photons. Our approach allows the use of ordinary (linear) optical elements that are available for the most part as off-the-shelf components. Recent experimental demonstrations of a variety of logic gates for single photons, a prototype memory device, and other devices will be described.

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Colloquium Speaker: James D. Franson

Dr. James Franson is a member of the Principal Professional Staff at APL as well as a Research Professor in the Johns Hopkins Department of Electrical and Computer Engineering. He received a bachelor's degree in physics from Purdue University in 1970 and a Ph.D in physics from Caltech in 1977. He is a Fellow of the Optical Society of America. His research interests include quantum computing, quantum cryptography, and quantum optics.