Laser used to observe and control electron spin

MIT researchers showed that laser can be used to observe electrons spin and even control the electrons movement using polarization. This could lead to a very fast spintronics devices.

The team devised a method that can provide a detailed three-dimensional mapping of the electron energy, momentum and spin states all at once. They did this by using short, intense pulses of circularly polarized laser light whose time of travel can be precisely measured. Using this method they were able to image how the spin and motion are related, for electrons travelling in all different directions and with different momenta, all in a fraction of the time it would take using alternative methods.

The team also discovered that instead of the spin being precisely aligned perpendicular to the direction of the electrons’ motion, when the electrons moved with higher energies there was an unexpected tilt, a sort of warping of the expected alignment.

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Posted: Dec 06,2011 by Ron Mertens