[2Bp01-10] Surface Analysis/Applied Surface Science/Evaluation Technique (ASS)

[2Bp10] Effects of the ultra-high vacuum heating on oxidized germanene

*Seiya Suzuki¹, Daiki Katsube², Masahiro Yano¹, Yasutaka Tsuda¹, Tomo-o Terasawa¹, Hidehito Asaoka¹, Junji Yuhara³, Akitaka Yoshigoe¹ (1. Japan Atomic Energy Agency, 2. RIKEN, 3. Nagoya University)

Germanene is a two-dimensional (2D) sheet of germanium (Ge) with a honeycomb lattice. Recent theoretical studies have predicted several interesting electronic properties of germanene, such as 2D topological insulators. However, unlike graphene, germanene is easily oxidized in air, making it difficult to realize electrical devices based on germanene. To overcome the drawback of the chemical stability of germanene, it is necessary to understand how germanene is oxidized. Therefore, we started to study germanene and discovered an interesting phenomenon: oxidized germanene can be restored to good quality germanene simply by heating it in ultra-high vacuum (UHV). X-ray photoelectron spectroscopy spectra and low energy electron diffraction patterns indicate that the oxidized germanene is fully recovered after heating at 500 °C. The detailed mechanism of the recovery will be discussed in the presentation.