In 1884, a new physics laboratory opened at Harvard. It was based on the revolutionary idea that "the department of physics in a University must embrace both teaching and investigation" (John Trowbridge).
From those pioneering days and throughout the Department's long and illustrious history, its faculty and students have been engaged in groundbreaking research and standard-setting instruction, contributing importantly to Harvard's reputation as one of the premier institutions of higher learning in the world. Among Harvard's 43 Nobel laureates, 10 are or were physics faculty members. Today, the latest generation of Harvard physicists continues to bring new insights into the exploration of fundamental problems involving physics at all length scales, and to provide outstanding and innovative educational opportunities to the many talented men and women who enroll in Harvard's flexible undergraduate and graduate programs.
Movies of Electrons in Atoms
Atomic movie star. In a recent experiment, fast changes in the electron cloud around a krypton ion were inferred from the absorption of laser pulses [1]. A more direct movie of electron cloud motion could be made using attosecond pulses of electrons, according to new simulations.
Physicists have long been able to snap atomic-scale pictures by shining a beam of electrons at a target, but filming the electronic structure of an atom as it changes in time is the next goal. A rapid "strobing" of electron pulses less than a millionth of a billionth of a second long should do the trick, according to a theoretical analysis in the 31 December Physical Review Letters. The authors demonstrate with computer simulations that ultrafast electron pulses could track the "breathing" state of an excited atom or the hopping of electrons between atoms in a molecule. Such movies open up the possibility of controlling the electrons that drive chemical reactions
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