The search for topological excitations such as Majorana fermions has spurred interest in the boundaries between distinct quantum states. Here, we explore an interface between two prototypical phases of electrons with conceptually different ground states: the integer quantum Hall insulator and the s-wave superconductor. We find clear signatures of hybridized electron and hole states similar to chiral Majorana fermions, which we refer to as chiral Andreev edge states (CAESs). These propagate along the interface in the direction determined by the magnetic field and their interference can turn an incoming electron into an outgoing electron or hole, depending on the phase accumulated by the CAESs along their path. Our results demonstrate that these excitations can propagate and interfere over a significant length, opening future possibilities for their coherent manipulation.

寻找诸如马约拉那费米子之类的拓扑激发激发了人们对不同量子态之间边界的兴趣。在这里，我们探索具有概念上不同的基态的电子的两个原型阶段之间的界面：整数量子霍尔绝缘体和s波超导体。我们发现类似于手性马约拉那费米子的杂化电子和空穴状态的清晰特征，我们将其称为手性安德列夫边缘态（CAES）。它们沿着界面在由磁场确定的方向上传播，并且它们的干扰可以将入射的电子转换为出射的电子或空穴，这取决于CAES沿其路径累积的相位。我们的结果表明，这些激发可以在相当长的时间内传播和干扰，为它们的连贯操纵开辟了未来的可能性。