Optical constants

Refractive index of Si (Silicon)

Li 1980: n 1.2–14 µm; 750 K

Data
tabulated n
Range
1.2–14 µm
Points
35
State
crystalline
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 1.2–14 µm
Refractive index n
3.5135
Extinction coefficient k
0
Permittivity ε1
12.3447
Permittivity ε2
0
Absorption coefficient α
0 cm⁻¹
Penetration depth δ = λ/(2πk)
— nm
Abbe number Vd
—
Chromatic dispersion dn/dλ
-0.004 µm⁻¹
Group index ng
3.5299
Group velocity dispersion
— fs²/mm
Dispersion parameter D
— ps/(nm·km)
Photon energy
0.3024 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

# Si (Silicon): Li 1980: n 1.2–14 µm; 750 K
si = ls.fetch_refractiveindex("main", "Si", "Li-750K", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(si.range_nm)  # (1200, 14000) nm
eps = si.eps([4100])  # complex permittivity

Downloads the original record once (pinned to the imported snapshot) and caches it.

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

700 K (477 °C)

References

H. H. Li. Refractive index of silicon and germanium and its wavelength and temperature derivatives. J. Phys. Chem. Ref. Data 9, 561-658 (1993)
  • doi:10.1063/1.555624 Refractive index of silicon and germanium and its wavelength and temperature derivatives, Journal of Physical and Chemical Reference Data (1980)

Cite

H. H. Li. Refractive index of silicon and germanium and its wavelength and temperature derivatives. Journal of Physical and Chemical Reference Data, 9, 561-658 (1980), doi:10.1063/1.555624; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

35 rows as published
Si (Silicon), Li 1980: n 1.2–14 µm; 750 K: n and k versus wavelength
λ (µm)n
1.23.6252
1.223.6213
1.243.6176
1.263.614
1.283.6106
1.33.6074
1.323.6043
1.343.6013
1.363.5989
1.383.5957
1.43.5931
1.453.5871
1.53.5816
1.553.5766
1.63.5721
1.653.568
1.73.5643
1.83.5577
1.93.5521
2.03.5473
2.253.538
2.53.5313
2.753.5264
3.03.5226
4.03.5139
5.03.5099
6.03.5077
7.03.5063
8.03.5055
9.03.5049
10.03.5045
11.03.5042
12.03.5039
13.03.5037
14.03.5036

Optical transmission calculator

Free-standing sample in vacuum, normal incidence
Method
Transmittance T
—
Reflectance R
—

Fresnel reflection calculator

Direction
Rp
—
Rs
—
R = (Rp+Rs)/2
—
Phase φp
—
Phase φs
—
Brewster angle θB
—
Critical angle θC
—