Femtosecond laser-induced processes: ultrafast dynamics and reaction pathways for O2/Pd(111)

Tony F. Heinz; James A. Misewich; U. Hoefer; A. Kalamarides; S. Nakabayashi; P. Weigand; Martin Wolf

doi:10.1117/12.180852

21 July 1994 Femtosecond laser-induced processes: ultrafast dynamics and reaction pathways for O₂/Pd(111)

Tony F. Heinz, James A. Misewich, U. Hoefer, A. Kalamarides, S. Nakabayashi, P. Weigand, Martin Wolf

Proceedings Volume 2125, Laser Techniques for Surface Science; (1994) https://doi.org/10.1117/12.180852
Event: OE/LASE '94, 1994, Los Angeles, CA, United States

Abstract

The processes of desorption and dissociation for O₂ on Pd(111) under femtosecond laser irradiation have been investigated. Desorption is characterize by a high yield, a nonlinear fluence dependence, and a dominant subpicosecond feature in two-pulse correlation measurements. These observations are consistent with a process driven by the high substrate electronic temperature produced by the femtosecond laser pulse. The correlation measurements also reveal the existence of a weaker feature persisting >10 ps which is attributed to an enhancement of the desorption rate by adsorbate vibrational excitation. Under the same conditions where efficient desorption is occurring, an upper limit of 5% is found for the dissociation of molecular oxygen. This is in contrast to the high branching ratio for dissociation found in thermal activation and conventional photoactivation for the same system. Explanations for the anomalous branching ratio in the femtosecond surface chemistry for O₂/Pd(111) within a model involving multiple cycles of electronic excitation are examined.

Citation Download Citation

Tony F. Heinz, James A. Misewich, U. Hoefer, A. Kalamarides, S. Nakabayashi, P. Weigand, and Martin Wolf "Femtosecond laser-induced processes: ultrafast dynamics and reaction pathways for O₂/Pd(111)", Proc. SPIE 2125, Laser Techniques for Surface Science, (21 July 1994); https://doi.org/10.1117/12.180852

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available