The recent breakthrough in quantum computing research has unveiled a revolutionary discovery – the world’s first multiple Majorana zero modes (MZMs) in a single vortex of the superconducting topological crystalline insulator SnTe. Led by Prof. Junwei Liu from the Hong Kong University of Science and Technology (HKUST), alongside Prof. Jinfeng Jia and Prof. Yaoyi Li from Shanghai Jiao Tong University (SJTU), the collaborative research team has paved the way for a new pathway towards the realization of fault-tolerant quantum computers.
Majorana zero modes (MZMs) are zero-energy topologically nontrivial quasiparticles in superconductors that exhibit non-Abelian statistics, allowing for inequivalent braiding sequences. This distinguishes MZMs from ordinary particles such as electrons or photons, where different braiding always leads to the same final state. The distinct property of MZMs to resist local perturbations makes them an ideal candidate for robust fault-tolerant quantum computation.
While significant progress has been made in engineering artificial topological superconductors, the braiding and manipulation of MZMs have posed significant challenges due to their spatial separation, making the necessary movements for hybridization complex and difficult. The unique approach taken by the collaborative research team at HKUST and SJTU leveraged crystal symmetry to eliminate these bottlenecks, facilitating the coupling between multiple MZMs within a single vortex of the superconducting topological crystalline insulator SnTe.
The experimental group at SJTU observed notable changes in the zero-bias peak, a strong indicator of MZMs, in the SnTe/Pb heterostructure under tilted magnetic fields. The subsequent extensive numerical simulations conducted by the theoretical team at HKUST confirmed that the anisotropic responses to tilted magnetic fields were indeed attributed to crystal-symmetry-protected MZMs. By employing advanced techniques such as the kernel polynomial method, the team simulated large vortex systems with millions of orbitals, enabling further exploration of novel properties in vortex systems beyond crystal-symmetry-protected MZMs.
The groundbreaking discovery of multiple Majorana zero modes in a single vortex of SnTe opens up new possibilities for the detection and manipulation of crystal-symmetry-protected MZMs. These findings not only pave the way for the experimental demonstration of non-Abelian statistics but also lay the foundation for the development of new types of topological qubits and quantum gates based on crystal-symmetry-protected multiple MZMs. This research marks a significant advancement in the field of quantum computing and brings us closer to achieving fault-tolerant quantum computers with unprecedented capabilities.