Topological Superconductivity in a Planar Josephson Junction

Foundational theory for topological superconductivity in planar Josephson junctions. Shows that a 2DEG with spin-orbit coupling, proximitized by two superconducting leads, enters a topological phase when Zeeman field exceeds a critical value — especially robust at phase difference $\phi =\pi$. The critical current minimum provides an experimental diagnostic for the topological transition. This geometry avoids the strict field-alignment requirements of nanowire proposals.

Key Results

• Topological superconducting phase in planar 2DEG Josephson junction
• Phase difference $\phi =\pi$ maximizes topological region in parameter space
• Critical current minimum marks the topological phase transition
• First-order phase transition in ground-state phase difference
• Planar geometry advantages: easier fabrication, relaxed field alignment

Links

• Journal: Physical Review X
• arXiv: 1609.09482

Zoo Links

• planar-josephson-junction-qubit
• majorana-topological-qubit