Dimensionality-dependent type-II Weyl semimetal state in Mo0.25W0.75Te2

Weyl nodes and Fermi arcs in type-II semimetals (WSMs) have led to lots of exotic transport phenomena. Recently, Mo$_{0.25}$W$_{0.75}$Te$_{2}$ has been established as a WSM with points located near level, which offers an opportunity study its intriguing band structure by electrical measurements. Here, selecting special sample the thickness gradient across two- (2D) three-dimensional (3D) regime, we show strong evidences that is semimetal observing following two dimensionality-dependent features: 1) A chiral-anomaly-induced anisotropic magneto-conductivity enhancement, proportional square in-plane magnetic field (B$_{in}$$^{2}$); 2) An additional quantum oscillation thickness-dependent phase shift. Our theoretical calculations observed originates from Weyl-orbit-like scenario due unique Mo$_{0.25}$W$_{0.75}$Te$_{2}$. The situ dimensionality-tuned experiment new strategy search for WSMs.