Quantum Size-Dependent Splitting of Surface States in Mn Monolayer on Ag(111)

Yu-Tung Lin^1*, Guan-Yi Huang¹, Shun-Ping Chou¹, Chia-Ju Chen¹, Jung-Jung Su², Pin-Jui Hsu¹

¹Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
²Department of Physics, National Yang Ming Chiao Tung University, Hsinchu, Taiwan

* Presenter:Yu-Tung Lin, email:jeremylin0911@gmail.com

Using scanning tunneling microscopy, we identified two unoccupied states in a monolayer of Mn on Ag(111), located at 1.2 eV and 1.6 eV above the Fermi level. These states shift in energy depending on the island size. For islands smaller than 500 atoms, the states converge at 1.8 eV. Density functional theory (DFT) calculations suggest that these states originate primarily from the Mn d-orbitals, which hybridize with the Ag(111) substrate. This interaction leads to a splitting of the in-plane and out-of-plane d-orbitals, causing the observed energy shift and splitting.

Keywords: condensed matter physics, scanning tunneling microscopy, quantum size effect, 2D material, surface state