Ferromagnetism in moiréflat-band systems has been extensively studied in the first valence miniband of twisted MoTe_(2),while its controlled realization at higher moiréfillings remains largely unexplored,exc...Ferromagnetism in moiréflat-band systems has been extensively studied in the first valence miniband of twisted MoTe_(2),while its controlled realization at higher moiréfillings remains largely unexplored,except for very recent works reporting correlated magnetism near half filling of the second moiréband.Here,we investigate rhombohedral-stacked twisted MoTe_(2)/hBN/WSe_(2) heterostructures and uncover two distinct ferromagnetic(FM)regions:one centered near v_(h)≈3(half filling of the second moirévalence 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 WSe_(2) is hole-doped in the re-entrant FM region,consistent with partial charge transfer from MoTe_(2) to WSe_(2).We propose that electric-field–induced layer repopulation stabilizes the re-entrant ferromagnetic phase by pinning the effective MoTe_(2) filling near v_(h)≈3 while adding carriers to the remote WSe_(2) layer.Our results demonstrate that remote-layer population control is an effective tuning knob for magnetic ordering in higher moiréminibands,extending the design space for correlated spin–valley phases in transition metal dichalcogenide heterostructures.展开更多
基金supported by the National Key R&D Program of China(Grant Nos.2021YFA1400100 and 2021YFA1401400)the National Natural Science Foundation of China(Grant Nos.12550403,12174250 and 12141404)+2 种基金the Shanghai Jiao Tong University 2030 Initiative Program B(Grant No.WH510207202)support from JSPS KAKENHI(Grant Nos.21H05233 and 23H02052)the World Premier International Research Center Initiative(WPI),MEXT,Japan。
文摘Ferromagnetism in moiréflat-band systems has been extensively studied in the first valence miniband of twisted MoTe_(2),while its controlled realization at higher moiréfillings remains largely unexplored,except for very recent works reporting correlated magnetism near half filling of the second moiréband.Here,we investigate rhombohedral-stacked twisted MoTe_(2)/hBN/WSe_(2) heterostructures and uncover two distinct ferromagnetic(FM)regions:one centered near v_(h)≈3(half filling of the second moirévalence 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 WSe_(2) is hole-doped in the re-entrant FM region,consistent with partial charge transfer from MoTe_(2) to WSe_(2).We propose that electric-field–induced layer repopulation stabilizes the re-entrant ferromagnetic phase by pinning the effective MoTe_(2) filling near v_(h)≈3 while adding carriers to the remote WSe_(2) layer.Our results demonstrate that remote-layer population control is an effective tuning knob for magnetic ordering in higher moiréminibands,extending the design space for correlated spin–valley phases in transition metal dichalcogenide heterostructures.