Charge-transfer-induced re-entrant ferromagnetism in twisted-bilayer-MoTe₂/hBN/WSe₂

Ferromagnetism in moiré flat-band systems has been extensively studied in the first valence miniband of twisted MoTe₂, while its controlled realization at higher moiré fillings remains largely unexplored, except for very recent works reporting correlated magnetism near half filling of the second moiré band. Here, we investigate rhombohedral-stacked twisted MoTe₂/hBN/WSe₂ heterostructures and uncover two distinct ferromagnetic (FM) regions: one centered near v_h ≈ 3 (half filling of the second moiré valence miniband) at zero displacement field, and a re-entrant FM phase that emerges for v_h > 3 only under a finite out-of-plane electric field. These FM regions are separated by a narrow filling window with a strongly suppressed magnetic circular dichroism (MCD) response. Layer-sensitive exciton spectroscopy identifies that WSe₂ is hole-doped in the re-entrant FM region, consistent with partial charge transfer from MoTe₂ to WSe₂. We propose that electric-field–induced layer repopulation stabilizes the re-entrant ferromagnetic phase by pinning the effective MoTe₂ filling near v_h ≈ 3 while adding carriers to the remote WSe₂ layer. Our results demonstrate that remote-layer population control is an effective tuning knob for magnetic ordering in higher moiré minibands, extending the design space for correlated spin–valley phases in transition metal dichalcogenide heterostructures.