Valley-spin polarization at zero magnetic field induced by strong hole-hole interactions in monolayer WSe$_2$

Justin Boddison-Chouinard; Marek Korkusinski; Alex Bogan; Pedro Barrios; Philip Waldron; Kenji Watanabe; Takashi Taniguchi; Jarosław Pawłowski; Daniel Miravet; Pawel Hawrylak; Adina Luican-Mayer; Louis Gaudreau

arXiv · 2410.11653

Valley-spin polarization at zero magnetic field induced by strong hole-hole interactions in monolayer WSe$_2$

Justin Boddison-Chouinard·Marek Korkusinski·Alex Bogan·Pedro Barrios·Philip Waldron·Kenji Watanabe·Takashi Taniguchi·Jarosław Pawłowski·Daniel Miravet·Pawel Hawrylak·Adina Luican-Mayer·Louis Gaudreau

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Abstract

Monolayer transition metal dichalcogenides have emerged as prominent candidates to explore the complex interplay between the spin and the valleys degrees of freedom. The strong spin-orbit interaction and broken inversion symmetry within these materials lead to the spin-valley locking effect, in which carriers occupying the K and K' valleys of the reciprocal space must have opposite spin depending on which valley they reside. This effect is particularly strong for holes due to a larger spin-orbit gap in the valence band. By reducing the dimensionality of a monolayer of tungsten diselenide to 1D via electrostatic confinement, we demonstrate that spin-valley locking in combination with strong hole-hole interactions lead to a ferromagnetic state in which hole transport through the 1D system is spin-valley polarized, even without an applied magnetic field, and that the persistence of this spin-valley polarized configuration can be tuned by a global back-gate. This observation opens the possibility of implementing a robust and stable valley polarized system, essential for valleytronic applications.

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Justin Boddison-Chouinard, Marek Korkusinski, Alex Bogan, Pedro Barrios, Philip Waldron, Kenji Watanabe, Takashi Taniguchi, Jarosław Pawłowski, Daniel Miravet, Pawel Hawrylak, Adina Luican-Mayer, Louis Gaudreau. 2024-10-15. Valley-spin polarization at zero magnetic field induced by strong hole-hole interactions in monolayer WSe$_2$. https://arxiv.org/abs/2410.11653

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