@article{sun_yang_yang_kumar_vetter_xue_li_li_li_zhang_et al._2020, title={Visualizing Tailored Spin Phenomena in a Reduced-Dimensional Topological Superlattice}, volume={32}, ISSN={["1521-4095"]}, DOI={10.1002/adma.202005315}, abstractNote={Emergent topological insulators (TIs) and their design are in high demand for manipulating and transmitting spin information toward ultralow‐power‐consumption spintronic applications. Here, distinct topological states with tailored spin properties can be achieved in a single reduced‐dimensional TI‐superlattice, (Bi2/Bi2Se3)‐(Bi2/Bi2Se3)N or (□/Bi2Se3)‐(Bi2/Bi2Se3)N (N is the repeating unit, □ represents an empty layer) by controlling the termination via molecular beam epitaxy. The Bi2‐terminated superlattice exhibits a single Dirac cone with a spin momentum splitting ≈0.5 Å−1, producing a pronounced inverse Edelstein effect with a coherence length up to 1.26 nm. In contrast, the Bi2Se3‐terminated superlattice is identified as a dual TI protected by coexisting time reversal and mirror symmetries, showing an unexpectedly long spin lifetime up to 1 ns. The work elucidates the key role of dimensionality and dual topological phases in selecting desired spin properties, suggesting a promise route for engineering topological superlattices for high‐performance TI‐spintronic devices.}, number={49}, journal={ADVANCED MATERIALS}, author={Sun, Rui and Yang, Shijia and Yang, Xu and Kumar, A. and Vetter, Eric and Xue, Wenhua and Li, Yan and Li, Na and Li, Yang and Zhang, Shihao and et al.}, year={2020}, month={Dec} }
 @article{sun_yang_yang_vetter_sun_li_su_li_li_gong_et al._2019, title={Large Tunable Spin-to-Charge Conversion Induced by Hybrid Rashba and Dirac Surface States in Topological Insulator Heterostructures}, volume={19}, ISSN={["1530-6992"]}, DOI={10.1021/acs.nanolett.9b01151}, abstractNote={Topological insulators (TIs) have emerged as some of the most efficient spin-to-charge convertors because of their correlated spin-momentum locking at helical Dirac surface states. While endeavors have been made to pursue large "charge-to-spin" conversions in novel TI materials using spin-torque-transfer geometries, the reciprocal process "spin-to-charge" conversion, characterized by the inverse Edelstein effect length (λIEE) in the prototypical TI material (Bi2Se3), remains moderate. Here, we demonstrate that, by incorporating a "second" spin-splitting band, namely, a Rashba interface formed by inserting a bismuth interlayer between the ferromagnet and the Bi2Se3 (i.e., ferromagnet/Bi/Bi2Se3 heterostructure), λIEE shows a pronounced increase (up to 280 pm) compared with that in pure TIs. We found that λIEE alters as a function of bismuth interlayer thickness, suggesting a new degree of freedom to manipulate λIEE by engineering the interplay of Rashba and Dirac surface states. Our finding launches a new route for designing TI- and Rashba-type quantum materials for next-generation spintronic applications.}, number={7}, journal={NANO LETTERS}, author={Sun, Rui and Yang, Shijia and Yang, Xu and Vetter, Eric and Sun, Dali and Li, Na and Su, Lei and Li, Yan and Li, Yang and Gong, Zi-zhao and et al.}, year={2019}, month={Jul}, pages={4420–4426} }