Majorana zero modes (MZMs) are emergent zero-energy topological quasiparticles that are their own antiparticles^1,2. Detected MZMs are spatially separated and electrically neutral, so producing hybridization between MZMs is extremely challenging in superconductors^3,4. Here, we report the magnetic field response of vortex bound states in superconducting topological crystalline insulator SnTe (001) films. Several MZMs were predicted to coexist in a single vortex due to magnetic mirror symmetry. Using a scanning tunnelling microscope equipped with a three-axis vector magnet, we found that the zero-bias peak (ZBP) in a single vortex exhibits an apparent anisotropic response even though the magnetic field is weak. The ZBP can robustly extend a long distance of up to approximately 100 nm at the (001) surface when the magnetic field is parallel to the (\(1\bar{1}0\))-type mirror plane, otherwise it displays an asymmetric splitting. Our systematic simulations demonstrate that the anisotropic response cannot be reproduced with trivial ZBPs. Although the different MZMs cannot be directly distinguished due to the limited energy resolution in our experiments, our comparisons between experimental measurements and theoretical simulations strongly support the existence and hybridization of symmetry-protected multiple MZMs. Our work demonstrates a way to hybridize different MZMs by controlling the orientation of the magnetic field and expands the types of MZM available for tuning topological states.

马约拉纳零模 (MZM) 是涌现的零能量拓扑准粒子，它们是它们自己的反粒子^1,2 。检测到的 MZM 是空间分离且电中性的，因此在超导体中产生 MZM 之间的杂化极具挑战性^3,4 。在这里，我们报告了超导拓扑晶体绝缘体 SnTe (001) 薄膜中涡旋束缚态的磁场响应。由于磁镜对称性，预计多个 MZM 会共存于一个涡旋中。使用配备三轴矢量磁体的扫描隧道显微镜，我们发现即使磁场很弱，单个涡旋中的零偏置峰（ZBP）也表现出明显的各向异性响应。当磁场平行于 ( \(1\bar{1}0\) ) 型镜面时，ZBP 可以在 (001) 表面稳健地延伸长达约 100 nm 的长距离，否则它会显示出不对称分裂。我们的系统模拟表明，各向异性响应无法用平凡的 ZBP 重现。尽管由于我们的实验中能量分辨率有限，无法直接区分不同的 MZM，但我们的实验测量和理论模拟之间的比较有力地支持了对称保护的多个 MZM 的存在和杂交。我们的工作展示了一种通过控制磁场方向来混合不同 MZM 的方法，并扩展了可用于调整拓扑状态的 MZM 类型。