Speaker
Mr
Björn Salzmann
(Universität Fribourg)
Description
Tantalum disulphide (1$T$-TaS$_2$) is a layered material which hosts an insulating commensurate charge density wave (CCDW) at temperatures below ~165K. Recent investigations of 1$T$-TaS$_2$ have revealed the existence of a metastable metallic phase accessible from this CCDW phase by applying a laser- or current pulse. Here we present Scanning Tunnelling Microscopy and Spectroscopy (STM/STS) measurements on 1$T$-TaS$_2$ surfaces not exposed to such pulses which show the same metallic behaviour as the pulse induced phase over distances of hundreds of nanometres. Further analysis shows evidence of a change in top layer stacking in the metallic phase, in agreement with recent theoretical and experimental works.
Authors
Mr
Björn Salzmann
(Universität Fribourg)
Elina Hujala
(University of Fribourg)
Christopher Nicholson
(University of Fribourg)
Catherine Witteveen
(University of Zurich)
Fabian von Rohr
(University of Zurich)
Dr
Helmuth Berger
Baptiste Hildebrand
(University of Fribourg)
Claude Monney
(University of Fribourg)