Lecture Topic:

Topological Correlations Among Chiral Structure and Magnetic Helicity/Spirality

Lecturer:

Sang-Wook Cheong

Time:

December 17, 2019 (Tuesday) 15:00-17:00

Place:

Lecture hall 101, Graduate School Building, Zhongguancun Campus

Organizer:

Graduate School, School of Aerospace Engineering

Registration:

Log-in to WeChat enterprise of Beijing Institute of Technology— 第二课堂（The Second Lecture）— Choose No.293 in the Lecture Registration

【Lecture Information】

Transition metal dichalcogenides (TMDs) have been extensively investigated as 2D materials last decade. A large amount of transition metals (M) can be intercalated into the van der Waals gaps of a wide range of TMD materials, but a limited recent study in intercalated TMDs have been reported. The limited examples include FexTaS 2 crystals with x=1/4 and 1/3, which exhibit intriguing configurations of antiphase and/or chiral structural domains related to the ordering of intercalated M ions with 2a×2a and√3a×√3a superstructures, respectively. In addition, Cr1/3NbS 2 undergoes helical spin order below 133 K, and shows an interesting soliton-lattice behavior when in-plane magnetic fields are applied in the helical spin state. We have explored a series of chiral M1/3Ta(Nb)S(Se) 2 to investigate the topological correlations among chiral structure, magnetic helicity/spirality and their physical properties. These results as well as Moire patterns with self-twisted TMDs induced by intercalation will be discussed.