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【Abstract】

Recent developments in condensed matter physics have concentrated on the pursuit of fault-tolerant quantum computing systems through the exploration of topological superconductors and Majorana fermions. Integration of quantum Hall (QH) edge states with superconductors (SC) emerges as a critical avenue in this pursuit, prompting extensive investigation into QH/SC interfaces. Of particular interest are the chiral Andreev edge states (CAES) formed at these interfaces, which exhibit electron-hole interference detected at downstream contacts. However, the precise mechanism underlying Andreev conversion remains elusive. This study delves into the spin properties of CAES through selective spin-filtering of quasi-particles, unveiling a robust spin-orbit coupling which induces spin flip during the Andreev conversion process. We perform comprehensive studies on Andreev conversions between different spin-polarized scattering paths. Our findings shed light on the spin dynamics at QH/SC interfaces, offering insights into the formation of topological superconductors and Majorana bound states, thus advancing our understanding of quantum computing systems and spintronics.