Optical constants
Refractive index of GLS - Gallium lanthanum sulphide (CRYSTRAN)
GLS - Gallium lanthanum sulphide: n,k 0.5461–1.71 µm
- Data
- tabulated n + tabulated k
- Range
- 0.5461–1.71 µm
- Points
- 8
- State
- crystalline
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 2.49563
- Extinction coefficient k
- 0
- Permittivity ε1
- 6.22815
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.508475 µm⁻¹
- Group index ng
- 2.79441
- 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
# GLS - Gallium lanthanum sulphide (CRYSTRAN): GLS - Gallium lanthanum sulphide
crystran_gls = ls.fetch_refractiveindex("specs", "CRYSTRAN-optical", "GLS", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(crystran_gls.range_nm) # (546.1, 1710.1) nm
eps = crystran_gls.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_930c0e7db976/lightsmith"
crystran_gls = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(crystran_gls.source) # citation and provenance travel with the dataAny dataset here, as the library's Tabulated material (crystran-gls/crystran).
# ... load crystran_gls as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=crystran_gls)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=547, 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.
Comments and conditions
Properties
- density
- value: 4040
- thermal dispersion
- type: constant, value: 75e-06
- thermal expansion
- value: 10e-06, temperature: 273
- hardness
- type: Knoop, value: 2.02e9, indenter mass: 0.2
- melting point
- value: 1103
- thermal conductivity
- value: 0.43, temperature: 273
- youngs modulus
- value: 59e9
- poissons ratio
- value: 0.24
- solubility
- value: 0
Thermo-optic coefficient
- dn/dT = 7.50e-05 K⁻¹
References
See also Crystran GLS online data sheet
Cite
Crystran Ltd. The Crystran handbook of infra-red and ultra-violet optical materials (5th edition, 2023); See also Crystran GLS online data sheet; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
Computed on 8 wavelengths, the same grid as the API and the library| λ (µm) | n | k |
|---|---|---|
| 0.5461 | 2.522 | 0 |
| 0.579 | 2.5 | 0 |
| 0.6439 | 2.467 | 0 |
| 0.6678 | 2.458 | 0 |
| 0.7065 | 2.446 | 0 |
| 1.014 | 2.398 | 0 |
| 1.3673 | 2.379 | 0 |
| 1.7101 | 2.371 | 0 |
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
- —
Gallium Lanthanum Sulphide is a radically new chalcogenide glass and a much awaited alternative to toxic Arsenic-based glasses, with an optical transparency from the visible to infrared wavelengths, and thermal stability up to 550oC. In addition, GLS can be melted in a large scale without the need for sealed ampoule processing making GLS production and processing safer and more economical. Equally important, impurity levels, in particular, OH- and SH- absorption bands at around 3 and 4 ìm have been substantially reduced thus increasing performance.
GLS has found use in a wide range of optoelectronic applications and is available as polished optical components, thin and thick films and in optical fibre form.
Gallium Lanthanum Sulphide (GLS) glass is produced by proprietary processes under conditions of the highest purity. Particular effort is made in removing transition metal impurities to a level of better than 1 ppm total metallic impurities with SH- and OH- less than 1 ppm. GLS is routinely processed from ingots of 500 grams. Other glass compositions are available including rare earth doped (Ce, Pr, Nd, Tb, Dy, Ho, Er, Tm, Yb), halide (F, Cl), and Ag doped samples.
REFERENCES:
(1) Petrovich, Hewak et al Journal of Non-Crystalline Solids 326&327 (2003) 93–97°K-1