Ultrafast laser-induced phase transitions in amorphous GeSb films.
Time-resolved measurements of the spectral dielectric function reveal new information about ultrafast phase transitions induced by femtosecond laser pulses in Sb-rich amorphous GeSb films. The excitation generates a nonthermal phase within 200 fs. The dielectric function of this phase differs from that of the crystalline phase, contrary to previous suggestions of a disorder-to-order transition. The observed dielectric function is close to that of the liquid phase, indicating an ultrafast transition from the amorphous phase to a different disordered state.
Callan
J P
JP
Department of Physics and Division of Engineering and Applied Sciences, Gordon McKay Laboratory, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138, USA. paul_callan@post.harvard.edu
Kim
A M
AM
Roeser
C A
CA
Mazur
E
E
Solis
J
J
Siegel
J
J
Afonso
C N
CN
de Sande
J C
JC