Qubit ZooCurated map of Zoo entries in the Topological family.
Entries
| Entry | Type | Status |
|---|---|---|
| majorana-topological-qubit | qubit | demonstrated |
| planar-josephson-junction-qubit | qubit | proposed |
| tetron-qubit | qubit | proposed |
Composition
- qubit: 3
Three-layer map
- majorana-topological-qubit is the physics-layer note: nonlocal fermion-parity encoding, Majorana zero modes, and the requirement that splitting fall exponentially with separation.
- planar-josephson-junction-qubit is the fabrication-layer route: a lithographically defined InAs/Al-style junction where spin-orbit-coupling-for-qubit-control and phase bias near create a tunable topological channel.
- tetron-qubit is the architecture-layer proposal: four Majorana modes arranged for parity measurement and measurement-only braiding, with the long-term promise judged against threshold-theorem rather than spectroscopy alone.
What unifies this family
Topological notes in the Zoo should read as a stack, not as three unrelated devices. The common claim is hardware-level error suppression from nonlocal parity encoding, but the practical bottleneck is still the same divincenzo-criteria scorecard as everywhere else: prepare a protected state, read parity reliably, and execute entangling operations before quasiparticle poisoning or mode overlap erases the advantage.
Boundary with the super-semi family
The materials overlap with super-semi-moc on purpose, especially around InAs/Al weak links and Josephson geometries, but the classification hinge is different. Keep a note in Topological when the qubit claim depends on entering a topological superconducting regime and protecting information in nonlocal fermion parity. If the same hybrid hardware is being used mainly for gate-tunable Josephson physics, Andreev control, or protected-circuit engineering without a topological phase claim, it belongs in super-semi-moc instead.
Reading order
If you want the shortest conceptual path through this family, start with majorana-topological-qubit for the protection mechanism, then planar-josephson-junction-qubit for the scalable materials platform, and finish with tetron-qubit for the control architecture that tries to turn those ingredients into a computable qubit.