Screening dynamics in doped titanates
- Forschungszentrum Juelich (Germany); and others
The time scale for carrier relaxation in semiconductors is on the same order of magnitude as the life time of shallow core hole states (a few femtoseconds). Resonant Inelastic soft X-ray scattering (RIXS) which involves (virtual) excitations of core levels consequently contains information about the time development of the electronic structure on this time scale. In many cases one can treat the scattering in an absorption (SXA) followed-by-emission (SXE) picture, where simply the rates for various processes can be compared with the intermediate core hole state decay rate as an internal {open_quotes}clock{close_quotes}. By variation of x (0 < x < 1) in La{sub x}Sr{sub 1{minus}x}TiO{sub 3}, the amount of Ti d electrons in the system can be controlled. SrTiO{sub 3} (x=0) is an insulator with an empty Ti d band. With increasing x, electrons are doped into the Ti d-band, and LaTiO{sub 3} (x=1) is a Mott Hubbard insulator with a Ti 3d{sup 1} configuration. In this work the authors demonstrate that the rate for Ti 2p core hole screening in La{sub x}Sr{sub 1{minus}x}TiO{sub 3} is doping dependent. The screening rate increases with the availability of Ti 3d electrons, and they estimate it to be 3.8 x 10{sup 13}/sec in La{sub 0.05}Sr{sub 0.95}TiO{sub 3}.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- OSTI ID:
- 603544
- Report Number(s):
- LBNL-39981; ON: DE97007345; TRN: 98:009541
- Resource Relation:
- Other Information: PBD: Apr 1997; Related Information: Is Part Of Advanced light source: Compendium of user abstracts 1993--1996; PB: 622 p.
- Country of Publication:
- United States
- Language:
- English
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