Spin Photovoltaic Effect in Magnetic van der Waals Heterostructures

Tiancheng Song; Eric Anderson; Matisse Wei-Yuan Tu; Kyle Seyler; Takashi Taniguchi; Kenji Watanabe; Michael A. McGuire; Xiaosong Li; Ting Cao; Di Xiao; Wang Yao; Xiaodong Xu

doi:10.1126/sciadv.abg8094

arXiv · 2102.10818

Spin Photovoltaic Effect in Magnetic van der Waals Heterostructures

Tiancheng Song·Eric Anderson·Matisse Wei-Yuan Tu·Kyle Seyler·Takashi Taniguchi·Kenji Watanabe·Michael A. McGuire·Xiaosong Li·Ting Cao·Di Xiao·Wang Yao·Xiaodong Xu

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Abstract

The development of van der Waals (vdW) crystals and their heterostructures has created a fascinating platform for exploring optoelectronic properties in the two-dimensional (2D) limit. With the recent discovery of 2D magnets, the control of the spin degree of freedom can be integrated to realize 2D spin-optoelectronics with spontaneous time-reversal symmetry breaking. Here, we report spin photovoltaic effects in vdW heterostructures of atomically thin magnet chromium triiodide (CrI3) sandwiched by graphene contacts. In the absence of a magnetic field, the photocurrent displays a distinct dependence on light helicity, which can be tuned by varying the magnetic states and photon energy. Circular polarization-resolved absorption measurements reveal that these observations originate from magnetic-order-coupled and thus helicity-dependent charge-transfer exciton states. The photocurrent displays multiple plateaus as the magnetic field is swept, which are associated with different spin configurations enabled by the layered antiferromagnetism and spin-flip transitions in CrI3. Remarkably, giant photo-magnetocurrent is observed, which tends to infinity for a small applied bias. Our results pave the way to explore emergent photo-spintronics by engineering magnetic vdW heterostructures.

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Tiancheng Song, Eric Anderson, Matisse Wei-Yuan Tu, Kyle Seyler, Takashi Taniguchi, Kenji Watanabe, Michael A. McGuire, Xiaosong Li, Ting Cao, Di Xiao, Wang Yao, Xiaodong Xu. 2021-02-22. Spin Photovoltaic Effect in Magnetic van der Waals Heterostructures. https://doi.org/10.1126/sciadv.abg8094

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