UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Quantum dynamics of STM and laser induced desorption of atoms and molecules from surfaces

Boendgen, Gisela; (2000) Quantum dynamics of STM and laser induced desorption of atoms and molecules from surfaces. Doctoral thesis (Ph.D), UCL (University College London). Green open access

[thumbnail of Quantum_dynamics_of_STM_and_la.pdf] Text
Quantum_dynamics_of_STM_and_la.pdf

Download (10MB)

Abstract

The manipulation of atoms and molecules at solid surfaces by electronic excitations with electrons (or holes) emitted from the tip of a scanning tunneling microscope (STM) or with laser radiation is both of applied and fundamental interest, e.g. for micro- and nanostructuring of materials, the clarification of elementary (catalytic) reaction mechanisms and for the question of how to treat the quantum dynamics of a laser or STM driven "system" (the adsorbate) in contact with a dissipative (energy-withdrawing) "bath" (the substrate). Desorption induced by electronic transitions (DIET) and its variant DIMET (M = multiple) are among the simplest possible "reactions" of adsorbate-surface systems; usually involving extremely short-lived electronically excited intermediates. In this thesis, the ultra-short dynamics of directly (localised to the adsorbate-substrate complex) and indirectly (i.e., through the substrate) stimulated DIET and DIMET processes was studied for Si(100)-(2x1):H(D) and Pt(111):NO. Isotope effects and the influence of substrate temperature and applied electric fields on the desorption yields were examined and possibilities to actively control the outcome (e.g. yields, isotope ratios), for example by laser shaping techniques, were investigated. For that purpose, time-dependent wave packet methods and open system density matrix theory were used to account for energy dissipation and thus resulting ultrashort lifetime of the electronically excited states involved.

Type: Thesis (Doctoral)
Qualification: Ph.D
Title: Quantum dynamics of STM and laser induced desorption of atoms and molecules from surfaces
Open access status: An open access version is available from UCL Discovery
Language: English
Additional information: Thesis digitised by ProQuest.
Keywords: Pure sciences; Scanning tunneling microscope
URI: https://discovery.ucl.ac.uk/id/eprint/10106318
Downloads since deposit
33Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item