28/11/2016
Title: Chiral solitons for topological informatics
Speaker: 염 한 웅 교수님 (Center for Artificial Low Dimensional Electronic Systems,(IBS) / POSTECH )
Date & Time: Nov. 30(Wed.) 2016, 4:30 PM
Place: Natural Science 1, Room No. 31214
Abstract: Storing and manipulating information in robust ways is of prime interest in wide areas of science and technology. Using topologically protected local excitations, such robust imformatics may be realized. In magnetic information processing, the recent interest is focused on topological excitations of spins such as skyrmions. In electronic systems, Mayorana Fermions of topological edge states are expected to realize topological quantum computation. This talk reviews our recent approach to this issue, dealing with new types of solitons in an electronic system, which are realized in an indium atomic wire array on Si(111) in its charge density wave ground state [1]. Due to the wire’s unique double Peierls chain structure, this system constitutes an unprecedented Z4 topological insulator and its edge states are three distinct solitons with chiral dimension [2]. These chiral solitons can store quarternary bit information protected topologically. Moreover, the switching between solitons is observed, which corresponds to the algebraic operation embedded into the Z4 topology [3]. This system may provide a novel device platform for topological multi-bit informatics.
[1] T.-H. Kim and H. W. Yeom, Phys. Rev. Lett. 109, 246802 (2012).
[2] S. M. Cheon, S.-H. Lee, T.-H. Kim and H. W. Yeom, Science 350, 6257 (2015).
[3] T.-H. Kim, S. M. Cheon, and H. W. Yeom, under review.