Optical control of yields of CO photodesorbed from Cu(001) by chirped light pulses: density matrix theory and calculations

Yields of CO photodesorbed from Cu metal surfaces by absorption of femtosecond chirped pulses of visible light are obtained within a density matrix approach, including the non-linear optical response of the substrate for pulses of large fluence. Our model is based on potential energy surfaces, couplings and transition dipoles parametrized from electronic structure calculations for CO/Cu. Results show that the yields of desorbed CO can be controlled by both positive and negative chirping, to obtain either a suppression or an enhancement of the yield. The effect can be as large as a doubling of the yields.