Thursday 20 May 2010
Working in Ottawa today --Quantum Optics
Good morning folks,
I will be working today in Ottawa.
More fun than the dentist, but a pale comparison to being on a golf course.
And a special news item for propeller heads: Physicists at the Max Planck Institute of Quantum Optics have created a system based on a single atom that they’re calling a ”quantum optical transistor.” The transistor could someday serve as part of a quantum computer or as a node of a quantum data network.
Their process relies on a complex light manipulation technique called electromagnetically induced transparency (EIT). In EIT, one beam of light controls the properties of another, much as the gate voltage controls current through a regular transistor. The researchers demonstrated EIT through the mediation of a single atom, which is a first; previously the technique was applied to hundreds of thousands of atoms in a gas.
Normally, laser beams don’t interact with one another, but under certain conditions, you can force them to. The German researchers started by placing a rubidium atom in an optical cavity—two tiny mirrors spaced just half a millimeter apart. They aimed a laser into the cavity, tuning it so that the atom inside reflected it. They then fired a second laser of a different frequency, called the control laser, into the cavity at a right angle to the first. Tuning the second laser just so let them ”create the condition of transparency,” says Figueroa: The first laser’s light sailed right through. That gave the cavity system two states, transparent and opaque, analogous to the on-off states of a classical transistor.
Yes, very cool beans!
Have a good day, interact often.
Sent from my BlackBerry wireless handheld -- Envoyé de mon sans fil portatif BlackBerry