Berlin 2018 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 50: HL Poster IV
HL 50.49: Poster
Donnerstag, 15. März 2018, 19:00–21:00, Poster B
Spin dependent giant junction resistance in Fe/p-Si Schottky heterojunction — •Anirban Sarkar1,2, Amal Kumar Das2, and Thomas Brückel1 — 1Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Sciences JCNS and Peter Grünberg Institute PGI, JARA-FIT, 52425 Jülich, Germany. — 2Department of Physics, Indian Institute of Technology Kharagpur, West Bengal 721302, India.
We report on the giant positive magnetoresistive behavior of a simple Fe/p-Si Schottky heterojunction diode at low temperatures. The device shows good rectifying characteristics at room temperature and a dual - Schottky as well as magnetic diode - characteristics at low temperature (<50 K). Large change in the junction magnetoresistance value of 104% at 10 K is observed which saturates at a relatively low magnetic field (∼0.5 kOe). Quantitative analysis of the field dependence of the diode forward characteristic, reveal a spin diffusion length of 100 nm with a spin life-time of 300 ps.
Formation of a magnetic field dependent potential barrier at the interface, due to electrical injection of spin-polarized carriers from the ferromagnetic electrode into the semiconductor template is often referred to result in such large junction resistance. However, there lacks a proper experimental evidence to such models and therefore we propose that probing the depth profile of magnetization with polarized neutron reflectrometry (PNR) can reveal more information about the magnetic properties near the interface of such ferromagnetic/semiconductor heterostructures.