לוח שנה משולב

Molecules in the gas or liquid phases are generally randomly distributed and isotropically oriented in space. Thus, the determination and the measurement of chemical reaction rates or of optical properties requires, by necessity, averaging over all orientations. Femtosecond laser pulses enable molecular manipulation on time scales faster than the internal rotational and vibrational degrees of freedom, opening the way to the direct addressing of aligned and oriented molecules.
In this talk I will review molecular alignment and control, and will discuss selective excitation of like species. Our recent observation of the creation of unidirectional molecular rotation by a sequence of laser pulses and its observation by the rotational Doppler Effect will be described. Time permitting, I will also present predictions for the formation of vortices driven by the laser induced rotational motion of the molecules.