We theoretically investigate spin- and valley-polarized transport in planar heterostructures of transition metal dichalcogenides under modulations of off-resonant circularly polarized light, magnetic exchange fields, and gate voltage. We find that the antiferromagnetic exchange field can not only modulate different spin states, which resembles the role played by the ferromagnetic exchange field, but also dramatically change the effective band gap of a specific spin state, enabling the generation of spin polarization over a wider energy range. Off-resonant circularly polarized light tunes different valley states and the effective gap of a specific valley state, thereby generating a wide energy range for valley polarization. In the presence of both the antiferromagnetic exchange field and off-resonant circularly polarized light, the intrinsic band offset of the planar heterostructure and the external gate voltage can further tune the effective band structure, thereby tailoring the Fermi energy window for perfect spin and valley polarizations. Antiferromagnetic modulation and off-resonant circularly polarized light effectively change the band gap of different valley and spin states, making it possible for planar heterostructures of two-dimensional materials to be further applied to spintronic devices, valleytronic devices, and spin-valley filtering.

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• Spintronics
• Valleytronics
• 2-dimensional systems
• Transition metal dichalcogenides
• Landauer formula
• Transfer matrix method