Optical constants
Refractive index of Ar (Argon)
Larsén 1934: n 0.230–0.568 µm
- Data
- tabulated n
- Range
- 0.2303–0.5677 µm
- Points
- 17
- Temperature
- 273.15 K
- State
- gas
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 1.00029
- Extinction coefficient k
- 0
- Permittivity ε1
- 1.00058
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -7.13913e-05 µm⁻¹
- Group index ng
- 1.00032
- Group velocity dispersion
- — fs²/mm
- Dispersion parameter D
- — ps/(nm·km)
- Photon energy
- 3.42498 eV
ε = (n + ik)², α = 4πk/λ, ng = n − λ dn/dλ, GVD = λ³/(2πc²) d²n/dλ², D = −(λ/c) d²n/dλ². Group-velocity dispersion is given for formula data only.
Use it in Lightsmith
Load this data in Python, simulate in one more line
pip install lightsmith
import lightsmith as ls
# Ar (Argon): Larsén 1934: n 0.230–0.568 µm
ar = ls.fetch_refractiveindex("main", "Ar", "Larsen", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(ar.range_nm) # (230.283, 567.74) nm
eps = ar.eps([362]) # complex permittivityDownloads the original record once (pinned to the imported snapshot) and caches it.
import json, urllib.request
import lightsmith as ls
url = "https://materials.lightsmith.dev/v1/datasets/ds_f8138aca309b/lightsmith"
ar = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(ar.source) # citation and provenance travel with the dataAny dataset here, as the library's Tabulated material (ar/larsen-1934).
# ... load ar as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=ar)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=567, num=81),
)
res = ls.solve(sim) # exact Mie for a sphere
print(res.q_ext) # extinction efficiency at each wavelengthSame spec runs with DDA, FDTD, BEM or T-matrix: ls.compare(sim, ["mie", "dda"]).
Lightsmith is open source (MIT): Mie, T-matrix, BEM, DDA, FDTD, RCWA, TMM, mode solvers and inverse design behind one spec, on CPU or GPU. GitHub.
Comments and conditions
Conditions
- temperature
- 273.15 K
- pressure
- 101325
References
- doi:10.1007/bf01343498 Beitrag zur Dispersion der Edelgase, Zeitschrift f�r Physik (1934)
Cite
Tage Lars�n. Beitrag zur Dispersion der Edelgase. Zeitschrift f�r Physik, 88, 389-394 (1934), doi:10.1007/bf01343498; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
17 rows as published| λ (µm) | n |
|---|---|
| 0.230283 | 1.000309311 |
| 0.234617 | 1.000307956 |
| 0.238074 | 1.000306977 |
| 0.244765 | 1.000305164 |
| 0.246481 | 1.000304718 |
| 0.257707 | 1.000302107 |
| 0.267578 | 1.000300115 |
| 0.27536 | 1.000298742 |
| 0.276054 | 1.000298605 |
| 0.289445 | 1.000296522 |
| 0.292625 | 1.000296083 |
| 0.334244 | 1.000291437 |
| 0.380272 | 1.000288151 |
| 0.410925 | 1.000286541 |
| 0.491741 | 1.000283764 |
| 0.546225 | 1.00028255 |
| 0.56774 | 1.000282175 |
Optical transmission calculator
Free-standing sample in vacuum, normal incidence- Transmittance T
- —
- Reflectance R
- —
Fresnel reflection calculator
- Rp
- —
- Rs
- —
- R = (Rp+Rs)/2
- —
- Phase φp
- —
- Phase φs
- —
- Brewster angle θB
- —
- Critical angle θC
- —
Standard conditions: 0 °C, 760 torr (101.325 kPa).