Super-Semi MOC

Curated map of Zoo entries in the Super-Semi family.

Entries

Entry	Type	Status
all-semiconductor-superconducting-qubit	qubit	proposed
andreev-spin-qubit	qubit	demonstrated
ferbo-qubit	qubit	active
gatemon	qubit	demonstrated
gatemonium	qubit	demonstrated

Composition

• qubit: 5

Conceptual anchors

• josephson-junction-as-nonlinear-element is the shared superconducting backbone, even when the weak link is semiconductor-defined rather than oxide-barrier-defined.
• spin-orbit-coupling-for-qubit-control is the key separator between purely gate-tunable Josephson devices and spin-active Andreev hybrids.
• charge-noise-sweet-spot is the right lens for comparing how much electrical tunability each architecture gains without paying too much dephasing cost.
• noise-bias-and-asymmetric-error-channels is the extra routing note for the protection-first branch, where the claim is not just “higher coherence” but a deliberately skewed error channel.

Curated synthesis

The cleanest way to read this family is to ask where the semiconductor is doing the conceptual work. The same InAs/Al or group-IV vocabulary can mean three very different things.

1. Semiconductor as a tunable Josephson knob

   • gatemon is the minimal case: transmon logic survives, but the weak link makes $E_J$ electrically tunable.
   • gatemonium is the protected-circuit extension of the same move: the weak link still tunes the Josephson element, but now inside a fluxonium-style inductive circuit where gate control moves the device between different protection regimes.
   • Read this branch primarily through josephson-junction-as-nonlinear-element and charge-noise-sweet-spot, not through spin language.

2. Semiconductor as part of the qubit subspace itself

   • andreev-spin-qubit uses spin-split Andreev levels as the qubit degree of freedom, so spin-orbit physics and parity stability are the central story rather than side constraints.
   • ferbo-qubit pushes further into the protection-first regime: the Andreev sector is part of the mechanism that suppresses relaxation before error correction, which is why it belongs adjacent to noise-bias-and-asymmetric-error-channels as well as to superconducting protected-circuit notes.
   • This branch should feel closer to “engineered weak-link quantum states” than to ordinary tunable transmons.

3. Semiconductor as the full materials stack

   • all-semiconductor-superconducting-qubit is the fabrication-endpoint branch. Its main claim is not a new control Hamiltonian but the possibility of moving the entire superconducting circuit, junctions included, inside one doped crystal.
   • Compare it to gatemon or transmon on interface elimination and process integration, and to kane-qubit on atomic-precision fabrication lineage.

Routing rule inside the family

• Start with gatemon or gatemonium when the interesting question is what electrostatic control does to an otherwise familiar superconducting circuit.
• Start with andreev-spin-qubit or ferbo-qubit when the weak link’s internal spin, parity, or Andreev structure is the qubit resource or the protection mechanism.
• Start with all-semiconductor-superconducting-qubit when the value proposition is monolithic fabrication or interface elimination rather than a mature coherence result.
• For the non-hybrid dot and donor branch of the same broader materials ecosystem, continue in semiconducting-moc.

Boundary with the superconducting family

This family shares a lot of vocabulary with superconducting-moc, especially around Josephson elements, circuit-QED readout, and sweet-spot language, but the routing rule is simple: stay here only when the semiconductor weak link is doing conceptual work. gatemon and gatemonium belong here because gate-tunable junction physics is the point, and andreev-spin-qubit / ferbo-qubit belong here because Andreev-level and parity structure enter the qubit itself. If the main story is instead protected-circuit geometry, bosonic encoding, or ordinary superconducting coherence scaling, route back to superconducting-moc even when the fabrication stack overlaps.

Boundary with the topological family

This family shares hardware vocabulary with topological-moc such as InAs/Al heterostructures, Josephson weak links, and strong spin-orbit coupling, but it makes a different promise. gatemon, andreev-spin-qubit, and ferbo-qubit stay here because their value comes from tunability, Andreev structure, or circuit-level protection inside an otherwise conventional control stack. Once the central claim becomes nonlocal parity encoding or a phase-biased topological channel that is supposed to suppress errors before code overhead, route the reader to topological-moc instead.

Editorial note

This family is about hybridization, not mere material substitution. Keep links focused on what the semiconductor changes in the circuit physics, control surface, or protection story.