Seminar - Sanjoy K. Mahatha
Title: Absence of Dirac cones in monolayer silicene and multilayer Si films on Ag(111)
Info about event
Time
Talk by Sanjoy K. Mahatha
Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, I-34149 Trieste, Italy
Titel: Absence of Dirac cones in monolayer silicene and multilayer Si films on Ag(111)
Abstract: Honeycomb structured (4×4) monolayer silicene and (?3×?3)R30° multilayer silicon on Ag(111) have attracted a lot of interest with photoemission studies indicating the presence of ?-band Dirac cones near the Fermi level.1,2 In this talk, I will show instead that the ?-symmetry states of monolayer silicene lose their local character and the Dirac cones fade out. An interface state of free-electron-like Ag origin accounts for the spectral features that were attributed to silicene ?-bands.3,4 For multilayer silicon, the bands previously attributed to ?* state with Dirac fermion character are found to derive from the well-known Ag- (?3×?3)R30°-Si(111) structure, and from a Si modified Ag(111) interface states.5
1 P. Vogt et al., Phys. Rev. Lett. 108, 155501 (2012).
2 P. De Padova et al., Appl. Phys. Lett. 102, 163106 (2013), J. Phys.: Condens. Matter 25 382202 (2013).
3 D. Tsoutsou et al., Appl. Phys. Lett. 103, 231604 (2013).
4 S. K. Mahatha et al., Phys. Rev. B 89, 201416(R) (2014).
5 S. K. Mahatha et al., Phys. Rev. B 92, 245127 (2015).