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تسجيل مستخدم جديدLocal Real-Space View of the Achiral 1$T$-TiSe$_2$ 2 $times$ 2 $times$ 2 Charge Density Wave
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The transition metal dichalcogenide 1$T$-TiSe$_2$ is a quasi-two-dimensional layered material undergoing a commensurate 2 $times$ 2 $times$ 2 charge density wave (CDW) transition with a weak periodic lattice distortion (PLD) below $approx$ 200 K. Scanning tunneling microscopy (STM) combined with intentionally introduced interstitial Ti atoms allows to go beyond the usual spatial resolution of STM and to intimately probe the three-dimensional character of the PLD. Furthermore, the inversion-symmetric, achiral nature of the CDW in the $z$-direction is revealed, contradicting the claimed existence of helical CDW stacking and associated chiral order. This study paves the way to a simultaneous real-space probing of both charge and structural reconstructions in CDW compounds.
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A charge density wave (CDW) of a nonzero ordering vector $mathbf{q}$ couple electronic states at $mathbf{k}$ and $mathbf{k}+mathbf{q}$ statically, giving rise to a reduced Brillouin zone (RBZ) due to the band folding effect. Its structure, in terms o
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