Obiettivo Sources of polarized electrons based on photoelectronemission are very powerful tools in solid state physics, in atomic physics, in elementary particle physics, as well as in nuclear physics. In all these fields the number of investigations using beams of polarized electrons is increasing rapidly, because new insights into fundamental spin-dependent interactions between electrons and matter are possible. Up to now photocathodes made from bulk GaAs or its relatives have been used primarily for producing sources of polarized electrons. This material allows the emission of electrons spinpolarized to a degree of 50% only. New cathodes based on strained layers of III-V-semiconductors or on III-V-superlattice structures give polarization values above the 50% limit. First promising results are reported in the literature by American and Japanese groups. The goal of this project is the development of new types of photoemitters of polarized electrons. Encouraging data have already been produced. Investigations of strained GaAs- and GaAsP-cathodes produced by the loffe Institute in St. Petersburg reveal a spinpolarization of emitted electrons up to 88%, while the second Russian group in Novosibirsk has developed InGaAsP-cathodes that produce photoelectrons with a degree of polarization of 55%, so far at a high quantum efficiency. In the framework of the project the following work will be done: application of semiconductor photocathodes in sources of polarized electrons attached to an electron accelerator; measurement of spinpolarization spectra, of yield spectra, and of life time of photocathodes developed in the project; research on fundamental physics of photoelectron emission from solids; development of new schemes for the production of highly polarized electrons; growth of strained layer III-V-photocathodes and III-V-superlattice structures by MOCVD-techniques; growth of GaAsP-cathodes with optimum of spinpolarization of emitted electrons tuned to powerful laser radiation; theoretical calculations of semiconductor heterostructures suited to spinpolarized photoelectron emission; growth of semiconductor heterostructures applied in spinpolarized photoelectron emission by using liquid phase epitaxy; research on spinpolarized photoemission from III-V-semiconductor compounds; and study of time evolution of the photoemission process. Programma(i) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Argomento(i) 15 - Condensed Matter Physics Invito a presentare proposte Data not available Meccanismo di finanziamento Data not available Coordinatore JOHANNES GUTENBERG UNIVERSITÄT MAINZ Contributo UE Nessun dato Indirizzo Staudinger Weg 7 55099 Mainz Germania Mostra sulla mappa Costo totale Nessun dato Partecipanti (6) Classifica in ordine alfabetico Classifica per Contributo UE Espandi tutto Riduci tutto Ecole Polytechnique Francia Contributo UE Nessun dato Indirizzo 91128 Palaiseau Mostra sulla mappa Costo totale Nessun dato Politecnico di Milano Italia Contributo UE Nessun dato Indirizzo Piazza Leonardo da Vinci 32 20133 Milano Mostra sulla mappa Collegamenti Sito web Opens in new window Costo totale Nessun dato Russian Academy of Sciences Russia Contributo UE Nessun dato Indirizzo 194021 St. Petersburg Mostra sulla mappa Costo totale Nessun dato Russian Academy of Sciences - Siberian Branch Russia Contributo UE Nessun dato Indirizzo 630090 Novosibirsk Mostra sulla mappa Costo totale Nessun dato St. Petersburg State Technical University Russia Contributo UE Nessun dato Indirizzo 195251 St. Petersburg Mostra sulla mappa Costo totale Nessun dato Stichting voor Fundamenteel Onderzoek der Materie Paesi Bassi Contributo UE Nessun dato Indirizzo 1009 DB Amsterdam Mostra sulla mappa Costo totale Nessun dato