Dimensionality-driven orthorhombic MoTe2 at room temperature

Abstract

We use a combination of Raman spectroscopy and transport measurements to study thin flakes of the type-II Weyl semimetal candidate MoTe2 protected from oxidation. In contrast to bulk crystals, which undergo a phase transition from monoclinic to the inversion symmetry breaking, orthorhombic phase below ~250 K, we find that in moderately thin samples below ~12 nm, a single orthorhombic phase exists up to and beyond room temperature. This could be due to the effect of c-axis confinement, which lowers the energy of an out-of-plane hole band and stabilizes the orthorhombic structure. Our results suggest that Weyl nodes, predicated upon inversion symmetry breaking, may be observed in thin MoTe2 at room temperature.

References in corpus (6)

• 2D materials and van der Waals heterostructures
• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Engineering the structural and electronic phases of MoTe2 through W substitution
• The extremely large magnetoresistance in the Candidate Type-II Weyl semimetal MoTe2
• Activation of new Raman modes by inversion symmetry breaking in type II Weyl semimetal candidate T'-MoTe2
• Hall-effect within the colossal magnetoresistive semi-metallic state of MoTe2

Cited by in corpus (6)

• Structural Phase Transition and Interlayer Coupling in Few-Layer 1T' and Td MoTe2
• Experimental Progress on Layered Topological Semimetals
• Thickness dependent transition from the 1T${}^{\prime }$ to Weyl semimetal phase in ultrathin MoTe${}_2$: Electrical transport, Noise and Raman studies
• Topological phase transition in MoTe${}_2$: A Review
• Generation and detection of coherent longitudinal acoustic waves in ultrathin 1T'-MoTe2
• Photoinduced Interlayer Dynamics in T${}_d$-MoTe${}_2$: A Broadband Pump-Probe Study