As a part of the JST research Project, Associate Professor Hideo Kosaka and his co-workers demonstrated the tomographic observation of spin state of optically injected electrons for the first time in the world.
They demonstrate that the polarization coherence of light is transferred to the spin coherence of electrons, and confirm this by applying the developed tomographic Kerr rotation method to semiconductor quantum wells with precessing and non-precessing electrons. Spin coherence transfer and spin state tomography will provide a way to write and read a spin qubit in a solid-state device for quantum cryptography and distributed quantum computing. This research was conducted with the assistance from Senior Researcher Hiroshi Imamura(CREST-JST) and Assistant Professor Yoshiaki Rikitake (Sendai National College of Technology). The research achievement was published in British Science Journal Nature on 5 February, 2009.

Contact:

Associate Professor Kosaka Hideo Research Institute of Electrical Communication Tohoku univeresity
2-1-1 Katahira, Aoba-ku, Sendai 980-8577
Tel:+81-22-217-5072 Fax:+81-22-217-5071
E-mail:kosaka_AT_riec.tohoku.ac.jp (Replace _AT_ to @)