Fig. 1. Semiconductor nanowire/superconductor composite device^[7]

Fig. 2. Composite structure of Nb-InSb nanowire-Nb superconductor. (a) Device structure of Nb-InSb nanowire-Nb superconductor; (b) scanning electron microscope image of the device; (c) differential conductance curves^[8]

Fig. 3. Superconducting quantum interference experiment. (a) Optical imaging of the device; (b) schematic of the device; (c) energy dispersion with spin-orbit interaction^[9]

Fig. 4. Fe atomic chain/superconductor hybrid system. (a) Fe atomic chain/superconductor device; (b) band structure of linear Fe atomic chain; (c) topological superconducting phase as a function of exchange interaction; (d) model calculation of local density of states of atomic chain embedded into superconductor; (e) spatially resolved local density of states calculated by same model with different energies^[21]

Fig. 5. Homogeneous two-gap structure on Fe (Te,Se)^[23]. (a) Topographic imaging of (Te,Se), inset is crystal structure of Fe (Te,Se); (b) scanning tunneling spectroscopy and angle-resolved photoelectron spectroscopy of (Te,Se) surface; (c) scanning tunneling spectroscopy along the arrow in Fig.(a) ^[23]

Fig. 6. Superconductivity in topological insulator^[31,34]. (a) Differential conductance spectra of Bi₂Se₃ films at 4.2 K and 0.4 K; (b) Dirac point with binding energy of 0.45 eV; (c) differential conductance at the vortex center measured with spin-polarized tip

Fig. 7. Topological superconductivity and Majorana states ^[36]. (a) Topological superconductivity on the surface of FeTe_0.55Se_0.45; (b) magnetic field creates vortices in FeTe_0.55Se_0.45, which behave as boundaries for topological superconductivity on the surface

Fig. 8. Majorana device^[39]. (a) Electron micrograph; (b) differential conductance versus gate voltage at zero bias

Fig. 9. Spin polarization of Fe chains on Pb(110) at normal state^[22]. (a) Schematic; (b) topography of a typical Fe chain

Fig. 10. Epitaxial hybrid nanowire with end dot^[43]

Fig. 11. Schematic diagram of optical pump-probe technique^[57-58]

Fig. 12. Schematic of GaAs nanoresonator with embedded SQD^[56]

Fig. 13. Schematic of optical detection method of Majorana fermions^[62]. (a) Schematic of energy level coupling of the system; (b) Fe atom chain/Pb superconductor composite system coupled with SQD; (c) schematic of nanoresonator with embedded SQD

Fig. 14. Schematic of optical detection of Majorana fermions^[63]

Fig. 15. Schematic of SQD detecting a pair of Majorana fermions^[65]. (a) Structure of hybrid semiconductor/superconductor device; (b) two-level quantum dots are modified by Majorana mode to form modified states 0,nM, 0,nM+1,1,nM, and 1,nM+1; (c) energy-level diagram of a pair of Majorana fermions coupled to quantum dots