Emergent interacting phases in the strong-coupling limit of twisted M-valley moiré systems: application to SnSe2

Journal article : Letter

We establish twisted SnSe₂ as a tunable platform for simulating dimension-dependent correlated physics, distinct from conventional K-valley moiré systems. By constructing interacting Wannier models, we show that the stacking configuration dictates the effective lattice geometry. In AAstacked bilayers, a momentum-space nonsymmorphic symmetry constrains the single-particle hopping within each valley to be effectively one-dimensional, while still allowing fully two-dimensional interactions, thereby giving rise to an effective quasi-one-dimensional system. This dimensional reduction stabilizes exotic phases including dimerized states with finite residual entropy, valence bond solids, and quantum paramagnetism. Conversely, AB-stacking maps to a frustrated Kagome lattice; here, strong interactions drive the emergence of a classical spin liquid. The high tunability of this moiré system, which allows control over both the filling and interaction strength (via twist angle), renders twisted SnSe₂ a versatile platform for realizing a wide range of exotic correlated quantum phases.

Authors: Li, M-R; Calugaru, D; Jiang, Y; Pi, H; Fischer, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review B
• Volume: 114
• Issue: 5
• Article number: L051113
• Publication date: 2026-07-31
• Acceptance date: 2026-06-04
• DOI: 10.1103/htld-vgws
• EISSN: 2469-9969
• ISSN: 2469-9950
• Language: English
• Subtype: Letter