セミナー・シンポジウム

HiSORセミナー(物性セミナー合同

Tailoring of Spin-Split Metallic Surface States of 2D Alloys and Compounds on Silicon

日時 2015年11月13日 (金) 16:30~より1時間程度
場所 理学研究科 C212
講師 Alexander A. Saranin
(Institute of Automation and Control Processes, Vladivostok, Russia)

In the present study, we propose a strategy for tailoring the spin-split metallic surface states on. The main concept resides in taking the surfaces with spin-split non-metallic surface-state bands and by alloying them with suitable metals to obtain dense reconstructions with spin-split metallic bands. Validity of the approach is demonstrated with Bi/Si(111)√3×√3 alloyed with Na and Tl/Si(111)1×1 alloyed with Pb [1]. Recent results of the development of this approach are demonstrated on the formation of a number of 2D alloys and compounds on the Si(111) surface with metallic spin split states: (i) sandwichlike structure made of one monolayer of Tl and one monolayer of Sn on Si(111) [2], (ii) TlxBi1-x compound which represents a quasi-periodic tiling structures that are built by a set of tiling elements as building blocks and (iii) Si(111)2×2-(Au,Al) with unusual spin texture. We demonstrated that one atom layer Si(111)√3×√3-Tl,Pb exhibits a giant Rashba-type spin splitting of metallic surface-state bands together with two-dimensional superconductivity [3].

References
1. D. V. Gruznev, et al. Sci. Rep. 4, 04742-5, (2014).
2. D. V. Gruznev, et al. Phys. Rev. B 91, 035421?7, (2015).
3. A. V. Matetskiy, et al. Phys. Rev. Lett. 115, 147003-5, (2015).

問合せ先 木村昭夫(理学研究科)