Laser-Chilled Atoms Sit for Ultrafast Portrait
Physicists from the University of Michigan recently fired 70-fs pulses from a Ti:sapphire laser to control the random movements of atoms in a potassium-tantalite crystal. The laser was split in two beams, with one arriving at the crystal target a few picoseconds after the first. The first pulse created pairs of phonons -- "squeezed" particles of vibrational energy -- that scattered the second, weaker pulse as it passed through the crystal. By measuring the energy that continued through the crystal, physicists could visualize the crystal's atomic structure.
MORE FROM PHOTONICS MEDIA