Supercalc — Superconducting Properties Calculator

A static, browser-based calculator for superconducting thin-film properties, with a Star Trek: TNG / LCARS theme. No build step, no dependencies, no server-side code — deployable as-is on GitHub Pages.

⚠️ Disclaimer — advisory only, no warranty

Every number Supercalc produces is an approximate estimate from idealized models and literature values that are sample-, deposition-, and measurement-dependent. The results are advisory only and come with no warranty of any kind as to accuracy, completeness, or fitness for any purpose. Do not rely on them as the sole basis for any design, fabrication, procurement, safety, or financial decision. Verify every result against primary references and your own measurements before acting on it. Use is entirely at your own risk. See LICENSE for the full terms.

Panels

1. Surface impedance (Zmuidzinas 2012, Eq. 8) — six linked fields: critical temperature Tc, normal-state resistivity ρ, sheet resistance Rₙ, film thickness t, sheet kinetic inductance L□, and the gap ratio Δ/(k_B·Tc). Enter any three of {Tc, ρ, t, L□} and the rest solve by constraint propagation (Rₙ is a convenience field). The gap ratio defaults to 1.764 (BCS); leave it blank to solve it from four over-determined measured values. Click a saved lab film to prefill it — presets hold ρ and the gap constant, so changing thickness updates L□.

2. Density of states N₀ / pulse height — from the material gap (panel 1) plus a measured single-photon response: photon energy (or wavelength), inductor height and width (thickness is inherited from panel 1), loaded quality factor Q, phase pulse height θ in degrees, kinetic-inductance fraction αₖ, pair-breaking efficiency η_pb, and the Mattis–Bardeen factor S₂. Computes the single-spin density of states N₀ in both eV⁻¹·µm⁻³ and SI (J⁻¹·m⁻³). Bidirectional: enter θ to get N₀, or enter N₀ to get the predicted θ.

3. Material explorer — a periodic table of the ambient-pressure elemental superconductors. Each clickable cell shows its Tc (gold above 1.3 K, blue below). Click one to prefill panel 1 with a best-guess Tc and resistivity.

Physics

With Δ = (gap ratio)·k_B·Tc, Rₙ = 10·ρ[µΩ·cm]/t[nm], and the thin-film limit of Eq. 8:

L□[pH/sq] = ħ·Rₙ / (π·Δ) · 1e12
N₀        = η_pb·αₖ·S₂·Q·E / (4·Δ²·V·θ)      (V = h·w·t, θ in radians)

The default gap ratio is the BCS weak-coupling value 1.764; real films often deviate (the Zobrist 2019 Hf preset solves to ≈2.86), so it is adjustable.

References:

• J. Zmuidzinas, Superconducting Microresonators: Physics and Applications, Annu. Rev. Condens. Matter Phys. 3, 169 (2012) — Eq. 8.
• N₀ inversion follows the Mazin Lab MKIDopt responsivity model.

Stored data

All material data is pre-stored (no live fetch).

• Presets: UCSB Hf (Zobrist 2019, 10.1063/1.5127768), UCSB PtSi (Szypryt 2017, 10.1364/oe.25.025894), UCSB WHf.
• Elements: Tc and ρ for the 30 ambient-pressure elemental superconductors, preferring thin-film literature values over bulk where available; each is tagged film or bulk with a source. Resistivities are representative and approximate; several are unavailable (stored as null). See the disclaimer above.

Run locally

ES modules require HTTP (not file://):

python3 -m http.server 8000
# open http://localhost:8000

Test

Pure physics modules are unit-tested with Node's built-in runner:

npm test          # → node --test

Deploy (GitHub Pages)

Static site, no build step. Settings → Pages → Deploy from a branch → main → /(root). Pushing to main updates the live site.

License

BSD 3-Clause, with an additional advisory/no-warranty disclaimer for the scientific calculations — see LICENSE. The LCARS theme is an unaffiliated homage.