Large Inverse Spin Hall Effect in Co-Pt Spin-Valve Heterostructures

Under a perpendicular temperature gradient, a heterostructure of ferromagnetic insulator plus normal metal yields a voltage via the inverse spin Hall effect (ISHE). When a $f\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}m\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}g\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}c$ metal is used instead, though, it becomes tricky to evaluate the ISHE voltage. In systems with large spin-orbit interaction, the authors observe significantly enhanced ISHE signals, suggesting that exchange-bias structures can be effective for detecting spin currents. This study provides insight into engineering hybrid spintronic devices to generate, manipulate, and detect pure spin current.