Pith Number

pith:CKVMIHUW

pith:2026:CKVMIHUWCH5KICPSLB5H5HYS26

not attested not anchored not stored refs resolved

Fraxonium: Fractional fluxon states for qudit encoding

Gianluigi Catelani, Luca Chirolli, Luigi Amico, Uri Vool, Valentina Brosco

A superconducting circuit generalizes the fluxonium using fractional fluxon states for protected qudit encoding.

arxiv:2605.14586 v1 · 2026-05-14 · quant-ph · cond-mat.mes-hall

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\pithnumber{CKVMIHUWCH5KICPSLB5H5HYS26}

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Record completeness

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4 Citations open

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Claims

C1strongest claim

The system represents a generalization of the fluxonium and the low-energy states are constituted by fractional fluxon states, that we call fraxons, localized in the minima of a suitably designed Josephson potential.

C2weakest assumption

A suitably designed Josephson potential can be realized through Fourier engineering with multi-harmonic elements such that d low-lying fractional fluxon states remain well separated from the rest of the spectrum.

C3one line summary

Superconducting circuit hosts fractional fluxon states (fraxons) in a tailored Josephson potential to realize protected qudits with a STIRAP gate protocol.

References

146 extracted · 146 resolved · 2 Pith anchors

[1] All the branches are connected in parallel, with a fluxπ/2 between the four equal modular elements

[2] Ω3Ω#=Ω Ω3 |2⟩|1⟩|0⟩ |𝑢⟩ Ω!Ω#Ω 2023

[3] Tight-binding model Following [107], we can model the dynamics between the fluxon states localized in the minima of the effective transmon potential through a tight-binding approach. The fluxon states

[4] cos[φx −π(m−n)/2] −E J Dmn( √ 2σ) cos[2φx −π(m−n)/2],(D4) In the working regimeE J ≫E C, EL, the level spacing provided by √8ECEL is small compared toE J and a large number of Fock states is needed to

[5] P. W. Shor, Scheme for reducing decoherence in quan- tum computer memory, Phys. Rev. A52, R2493 (1995) 1995

Receipt and verification

First computed	2026-05-17T23:39:05.306737Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

12aac41e9611faa409f2587a7e9f12d79d615c5394e9a2d8bc89d0798e570dda

Aliases

arxiv: 2605.14586 · arxiv_version: 2605.14586v1 · doi: 10.48550/arxiv.2605.14586 · pith_short_12: CKVMIHUWCH5K · pith_short_16: CKVMIHUWCH5KICPS · pith_short_8: CKVMIHUW

Agent API

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Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/CKVMIHUWCH5KICPSLB5H5HYS26 \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 12aac41e9611faa409f2587a7e9f12d79d615c5394e9a2d8bc89d0798e570dda

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "c353e7a8c9d968ee2a78cd82b5d1db63d99f811af94f29fbb16752d74336a849",
    "cross_cats_sorted": [
      "cond-mat.mes-hall"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "quant-ph",
    "submitted_at": "2026-05-14T08:58:07Z",
    "title_canon_sha256": "4037bf72e185d244d638ca22ffc2b61450b2a22f9c477da0acfb113cdc563e81"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2605.14586",
    "kind": "arxiv",
    "version": 1
  }
}