Optical constants
Refractive index of Na (Sodium)
Inagaki et al. 1976: n,k 0.326–2.07 µm
- Data
- tabulated nk
- Range
- 0.326–2.066 µm
- Points
- 33
- State
- solid
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 0.0466862
- Extinction coefficient k
- 2.46892
- Permittivity ε1
- -6.0934
- Permittivity ε2
- 0.230529
- Absorption coefficient α
- 528002 cm⁻¹
- Penetration depth δ = λ/(2πk)
- 37.8786 nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.119231 µm⁻¹
- Group index ng
- 0.116746
- 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): Inagaki et al. 1976: n,k 0.326–2.07 µm
na = ls.fetch_refractiveindex("main", "Na", "Inagaki", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(na.range_nm) # (326, 2066) nm
eps = na.eps([633]) # 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_78a86b7f50ea/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/inagaki-1976).
# ... 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=1000, 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.
References
- doi:10.1103/physrevb.13.2305 Optical properties of solid Na and Li between 0.6 and 3.8 eV, Physical Review B (1976)
Cite
T. Inagaki, L. C. Emerson, E. T. Arakawa and M. W. Williams. Optical properties of solid Na and Li between 0.6 and 3.8 eV. Physical Review B, 13, 2305-2313 (1976), doi:10.1103/physrevb.13.2305; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
33 rows as published| λ (µm) | n | k |
|---|---|---|
| 0.326 | 0.0464 | 1.08 |
| 0.335 | 0.0495 | 1.14 |
| 0.344 | 0.0539 | 1.19 |
| 0.354 | 0.0583 | 1.25 |
| 0.365 | 0.0628 | 1.32 |
| 0.376 | 0.0689 | 1.38 |
| 0.387 | 0.0742 | 1.44 |
| 0.4 | 0.0794 | 1.5 |
| 0.413 | 0.0812 | 1.56 |
| 0.428 | 0.0815 | 1.64 |
| 0.443 | 0.0791 | 1.71 |
| 0.459 | 0.0745 | 1.8 |
| 0.477 | 0.0689 | 1.88 |
| 0.496 | 0.064 | 1.99 |
| 0.517 | 0.0587 | 2.1 |
| 0.539 | 0.0539 | 2.23 |
| 0.564 | 0.0495 | 2.36 |
| 0.59 | 0.0464 | 2.48 |
| 0.62 | 0.0442 | 2.62 |
| 0.653 | 0.0424 | 2.78 |
| 0.689 | 0.0418 | 2.96 |
| 0.729 | 0.0418 | 3.15 |
| 0.775 | 0.0424 | 3.4 |
| 0.827 | 0.0447 | 3.64 |
| 0.886 | 0.048 | 3.87 |
| 0.954 | 0.0515 | 4.23 |
| 1.033 | 0.0574 | 4.62 |
| 1.127 | 0.066 | 5.05 |
| 1.24 | 0.0787 | 5.59 |
| 1.378 | 0.0949 | 6.24 |
| 1.55 | 0.117 | 7.02 |
| 1.771 | 0.146 | 8.09 |
| 2.066 | 0.198 | 9.46 |
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
- —