Imaging of surface phonons on a sphere



Surface phonon wavepackets are generated on aluminium-coated transparent glass balls on irradiation with ultrashort light pulses. Delayed ultrashort probe light pulses are used to image the surface phonon propagation in real time by simply monitoring the modulation in the reflected probe beam intensity caused by the photoelastic effect. Imaging was achieved in the region of the phonon source and at the opposite pole of the sphere. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)