Strain induced topological transitions in twisted double bilayer graphene

Twistronics and moiré excitonic physics in van der Waals heterostructures

“…For example, Both graphene and TMD possess maximum elastic strains larger than 10% [29]. Strain can realize continuous band structure modulation [30,32,174,175], and inhomogeneous strain can creat local variation of bandgap [31,[176][177][178]. The stacking structures of twisted 2D vdW heterostructures enable sensitive and dynamic strain engineering of moiré potential landscape [167] and topological properties [33].…”

“…The relatively weak interlayer vdW force enables vdW materials to be exfoliated into atomically thin layers with outstanding physical properties as well as highly adjustable 2D structures [12]. A variety of methods [21,22] have been shown to efficiently regulate material properties, such as external field [23][24][25][26], doping [26][27][28], strain [29][30][31][32][33], integration with optical microcavity [34], and changing dielectric environment [35][36][37]. In semiconducting 2D materials, the significantly enhanced Coulomb interactions due to reduced dielectric screening and increased quantum confinement give rise to rich excitonic species, which are formed by tightly bound electron and hole pairs and could persist up to room temperature, showing strong light-matter couplings and many-body effects [38].…”

Strain-induced topological phase transition in ferromagnetic Janus monolayer MnSbBiS2Te2

“…36 This method of strain engineering has also been applied to bilayers, heterostructures, and bulk materials. [37][38][39][40][41][42] In addition, an external electric field has also been used to tune the properties of MBT-type materials. Cui et al predicted that the electric control of the topological magnetic phase can be observed in the Janus magnetic MnBi 2-Se 2 Te 2 /In 2 Se 3 heterostructure.…”