Optical constants
Refractive index of Na (Sodium)
Monin and Boutry 1974: n,k 0.254–0.620 µm
- Data
- tabulated nk
- Range
- 0.2536–0.62 µm
- Points
- 13
- Temperature
- 293 K
- State
- solid
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 0.0467143
- Extinction coefficient k
- 2.52171
- Permittivity ε1
- -6.35686
- Permittivity ε2
- 0.2356
- Absorption coefficient α
- 539292 cm⁻¹
- Penetration depth δ = λ/(2πk)
- 37.0857 nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.238095 µm⁻¹
- Group index ng
- 0.186619
- Group velocity dispersion
- — fs²/mm
- Dispersion parameter D
- — ps/(nm·km)
- Photon energy
- 2.11001 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
# Na (Sodium): Monin and Boutry 1974: n,k 0.254–0.620 µm
na = ls.fetch_refractiveindex("main", "Na", "Monin", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(na.range_nm) # (253.6, 620) nm
eps = na.eps([397]) # 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_19e1457c90a3/lightsmith"
na = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(na.source) # citation and provenance travel with the dataAny dataset here, as the library's Tabulated material (na/monin-boutry-1974).
# ... load na as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=na)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=620, 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
- 293 K
References
- doi:10.1103/physrevb.9.1309 Optical and photoelectric properties of alkali metals, Physical Review B (1974)
Cite
J. Monin and G. -A. Boutry. Optical and photoelectric properties of alkali metals. Physical Review B, 9, 1309-1327 (1974), doi:10.1103/physrevb.9.1309; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
13 rows as published| λ (µm) | n | k |
|---|---|---|
| 0.2536 | 0.044 | 0.613 |
| 0.2654 | 0.042 | 0.713 |
| 0.2804 | 0.041 | 0.83 |
| 0.313 | 0.045 | 1.053 |
| 0.334 | 0.049 | 1.184 |
| 0.366 | 0.057 | 1.36 |
| 0.406 | 0.06 | 1.574 |
| 0.4358 | 0.062 | 1.741 |
| 0.46 | 0.063 | 1.86 |
| 0.4916 | 0.062 | 2.03 |
| 0.546 | 0.056 | 2.31 |
| 0.578 | 0.049 | 2.46 |
| 0.62 | 0.039 | 2.73 |
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
- —
293 K (19.85 °C)