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Updated: Feb 4, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
First-principles decoding of spin-valley-polarized H-phase TMDs: formation energies, magnetic ground states, and band
Shijie Guo1, Kai Cheng1, Guotai Zhang1
1School of Electronic Engineering, XI'AN University of Posts and Telecommunications, Xi'an 710121, China. chengkai_xiyou@163.com.
Abstract:
Using high-throughput GGA+U first-principles calculations we survey the formation energy, magnetic ground state and spin-valley-coupled electronic structure of 87 monolayer 2H-phase MX2 (M = Groups-IIIB-IIB, X = S, Se, Te). A systematic group-by-group evolution is uncovered: 3d-based TMDs favor antiferromagnetic (AFM) semiconductors, 4d congeners stabilize ferromagnetic (FM) metals or bipolar magnetic semiconductors (BMSs), whereas 5d members are overwhelmingly non-magnetic metals. Thermodynamic stability (ΔHf ≤ 0) is fulfilled for all sulfides/selenides/tellurides of Groups-IIIB-VIB and most of Groups-VIIB-VIII, whereas post-transition-metal TMDs (Groups IB-IIB) are unstable. Valley polarization is dictated by the interplay between hexagonal lattice symmetry and magnetic order: FM Group-VB VX2 and BMS VSe2/VTe2 exhibit 100% spin-polarized K/K' band edges ideal for the anomalous valley Hall effect, while AFM Group-VIB CrX2 and Mo/WX2 retain spin-degenerate K-point valleys suitable for reversible valleytronics. The resulting atlas provides an experimentally verifiable blueprint for wafer-scale synthesis of high-temperature FM, half-metallic or valley-polarized 2D crystals and accelerates the materialization of next-generation spin-valleytronic devices.
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