U Tokyo, Fujitsu Report Single-Photon Emission

TOKYO, July 19 -- The University of Tokyo's Nanoelectronics Collaborative Research Center and Fujitsu Laboratories Ltd. announced they have jointly developed technologies that generate and measure single photons and have observed emission of single photons in data transmission wavelengths.

The researchers said the new technologies pave the way for accelerating speeds for quantum encryption data transmission, considered the ultimate method of encrypted transmission, to 400 times faster than the data transmission speeds of conventional quantum encryption, which could only transfer data at a few hundred bits per second.

Details of the new technologies will be presented at The 27th International Conference on the Physics of Semiconductors (ICPS-27), to be held July 26-30 in Flagstaff, Ariz.

Partial research and development of the new technologies were supported by the Nano-Photonic and Electron Devices Technology Project, part of an information technology program of Japan's Ministry of Education, Culture, Sports, Science and Technology. The National Institute for Materials Science of Japan also participated.

"There is growing demand for higher-level security for data transmission with the ever-increasing use of electronic commerce over the Internet," Fujitsu Labs said in a press release. "In particular, transmission using quantum encryption, which is considered to be impossible to eavesdrop on and the ultimately secure method of encrypted transmission, is being actively studied and developed worldwide."

With the confirmation of single-photon transmission over conventional data transmission wavelengths, quantum encryption transmission is now possible without lowering the sender's light emission intensity, Fujitsu said. "This breakthrough enables transmission at speeds of 100 kilobits per second across a distance of approximately 100 kilometers, 400 times faster than conventional laser-sourced quantum encryption transmission. This dramatically increases the potential for the practical application of quantum encryption transmission technology for use at sites that require high-level data security."

The University of Tokyo and Fujitsu will promote further research to verify single-photon transmissions in 1.55 micron wavelengths; they said they aim to increase single-photon extraction efficiency, targeting realization of a practical single-photon generator by approximately 2007.

For more information, visit: www.labs.fujitsu.com/en/