We investigate thermal and nonlocal electrical transport in four-terminal Josephson junctions formed by a normal region coupled to two transverse chiral superconducting leads, supporting phases characterized by Chern numbers $\mathcal{C}=0,1$, and 2. For $\mathcal{C}=1$, we identify the conditions under which a single chiral Majorana mode, with equal superposition of electrons and holes, produces a robust half-integer quantized thermal conductance and a zero nonlocal electrical conductance. Thermal conductance quantization occurs near a superconducting phase difference $\pi$, but only in the low-doping regime of the central region and in the intermediate- to long-junction limits. At finite Zeeman fields, the thermal response broadly follows the topology of the isolated superconducting leads for the $C=1$ phase while, in the $\mathcal{C}=2$ phase, the thermal conductance generally deviates from quantization, depending on the momentum-space location of the Majorana modes. Our results establish clear criteria for probing chiral Majorana modes in Josephson junctions and highlight the essential role of momentum-space structure, finite-size geometry, and sample parameters in thermal transport.

Close

PrevNext

View figure in article

• Mesoscopics
• Thermal transport
• Topological phases of matter
• Superconductors