Three-way junction theory separates Majorana generation from transport
A theoretical study describes how a superconducting junction with three arms could create or route localized quantum states called Majorana bound states. Its calculations distinguish pair creation and annihilation from movement through the junction. The peer-reviewed paper also proposes a two-junction network and a way to investigate its behaviour through emitted radiation.
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Quantum states meet at three arms
A theoretical junction offers separate ways of producing and moving Majorana bound states, localized states with zero energy expected in certain quantum materials. The peer-reviewed Nature Communications paper models three Josephson links meeting on a topological insulator, a material with distinctive conducting surface states. Superconductors form the links, and a magnetic field points perpendicular to the surface. The calculations describe how the phases of the superconductors determine what happens at the centre.[1]
Creation and passage follow different regimes
In one regime, the junction centre serves as a source or sink: a pair of states appears or disappears there. In another regime, a state travels between an arm and the central region without a second state being created. A single straight link provides a track for movement; the meeting of three arms adds the possibilities of generating, removing and directing states. The distinction depends on which phase boundary the system crosses.[1]
A two-junction network has a proposed readout
The team also modelled a network with two junctions in which states can fuse and braid, meaning that their paths exchange positions. The proposal uses the spectrum of Josephson emission to investigate the resulting quantum evolution. This is an analytical and computational study of a specified arrangement. Experimental identification remains difficult because other physical mechanisms can mimic signals attributed to Majorana states.[1]
