Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(o) 0.7–12 µm; 500 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 500 K
- Optical axis
- o
- Licence
- CC0-1.0
Uniaxial crystal, axes: oe
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 3.17005
- Extinction coefficient k
- 0
- Permittivity ε1
- 10.0492
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0126003 µm⁻¹
- Group index ng
- 3.2066
- Group velocity dispersion
- 436.587 fs²/mm
- Dispersion parameter D
- -97.7857 ps/(nm·km)
- Photon energy
- 0.427532 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
# ZnGeP2 (Zinc germanium phosphide, ZGP): Ghosh 1998: n(o) 0.7–12 µm; 500 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-500K-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(zngep2.range_nm) # (700, 12000) nm
eps = zngep2.eps([2900]) # 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_535647149a1e/lightsmith"
zngep2 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(zngep2.source) # citation and provenance travel with the dataAny dataset here, as the library's Tabulated material (zngep2/ghosh-1998-500k-o).
# ... load zngep2 as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=zngep2)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=700, 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"]).
import json, urllib.request
import lightsmith as ls
url = "https://materials.lightsmith.dev/v1/datasets/ds_535647149a1e/lightsmith?model=drude_lorentz"
zngep2_dl = ls.DrudeLorentz.model_validate(json.load(urllib.request.urlopen(url)))A dispersive Drude–Lorentz model for time-domain solvers.
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.
Dispersion formula
Sellmeier (C in µm²) (formula 2), λ in µmValid from 0.7 to 12.0 µm.
Coefficients as stored
| Ci | Value |
|---|---|
| C1 | 3.70134287 |
| C2 | 5.274855 |
| C3 | 0.14650344 |
| C4 | 2.16991032 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 500 K
- direction
- o
References
G. Ghosh.
Sellmeier coefficients for the birefringence and refractive indices of ZnGeP2 nonlinear crystal at different temperatures.
Appl. Opt., 37, 1205-1212 (1998)
- doi:10.1364/ao.37.001205 Sellmeier coefficients for the birefringence and refractive indices of ZnGeP_2 nonlinear crystal at different temperatures, Applied Optics (1998)
Cite
Gorachand Ghosh. Sellmeier coefficients for the birefringence and refractive indices of ZnGeP_2 nonlinear crystal at different temperatures. Applied Optics, 37, 1205 (1998), doi:10.1364/ao.37.001205; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
Computed on 400 wavelengths, the same grid as the API and the library
CSV comma separated
TXT tab separated
YAML n, k
Full database record original YAML
All quantities CSV
JSON metadata
| λ (µm) | n |
|---|---|
| 0.7 | 3.496395 |
| 0.705003 | 3.489934 |
| 0.710042 | 3.483629 |
| 0.715117 | 3.477475 |
| 0.720228 | 3.471465 |
| 0.725375 | 3.465597 |
| 0.73056 | 3.459865 |
| 0.735781 | 3.454266 |
| 0.74104 | 3.448794 |
| 0.746336 | 3.443448 |
| 0.75167 | 3.438222 |
| 0.757043 | 3.433113 |
| 0.762453 | 3.428119 |
| 0.767903 | 3.423235 |
| 0.773391 | 3.418458 |
| 0.778919 | 3.413785 |
| 0.784486 | 3.409214 |
| 0.790093 | 3.404742 |
| 0.79574 | 3.400365 |
| 0.801427 | 3.396081 |
| 0.807155 | 3.391888 |
| 0.812924 | 3.387783 |
| 0.818734 | 3.383764 |
| 0.824585 | 3.379829 |
| 0.830479 | 3.375975 |
| 0.836414 | 3.3722 |
| 0.842392 | 3.368502 |
| 0.848413 | 3.36488 |
| 0.854477 | 3.36133 |
| 0.860584 | 3.357852 |
| 0.866735 | 3.354444 |
| 0.87293 | 3.351103 |
| 0.879169 | 3.347829 |
| 0.885452 | 3.344619 |
| 0.891781 | 3.341472 |
| 0.898154 | 3.338386 |
| 0.904574 | 3.33536 |
| 0.911039 | 3.332393 |
| 0.91755 | 3.329483 |
| 0.924108 | 3.326628 |
| 0.930713 | 3.323828 |
| 0.937365 | 3.321081 |
| 0.944064 | 3.318386 |
| 0.950812 | 3.315741 |
| 0.957607 | 3.313146 |
| 0.964451 | 3.3106 |
| 0.971345 | 3.308101 |
| 0.978287 | 3.305647 |
| 0.985279 | 3.30324 |
| 0.992321 | 3.300876 |
| 0.999413 | 3.298555 |
| 1.00656 | 3.296277 |
| 1.01375 | 3.29404 |
| 1.021 | 3.291843 |
| 1.02829 | 3.289686 |
| 1.03564 | 3.287568 |
| 1.04304 | 3.285487 |
| 1.0505 | 3.283444 |
| 1.05801 | 3.281437 |
| 1.06557 | 3.279465 |
| 1.07318 | 3.277528 |
| 1.08085 | 3.275625 |
| 1.08858 | 3.273755 |
| 1.09636 | 3.271918 |
| 1.1042 | 3.270112 |
| 1.11209 | 3.268338 |
| 1.12004 | 3.266595 |
| 1.12804 | 3.264881 |
| 1.1361 | 3.263197 |
| 1.14422 | 3.261542 |
| 1.1524 | 3.259915 |
| 1.16064 | 3.258316 |
| 1.16893 | 3.256744 |
| 1.17729 | 3.255198 |
| 1.1857 | 3.253678 |
| 1.19418 | 3.252184 |
| 1.20271 | 3.250715 |
| 1.21131 | 3.249271 |
| 1.21997 | 3.24785 |
| 1.22868 | 3.246453 |
| 1.23747 | 3.245079 |
| 1.24631 | 3.243728 |
| 1.25522 | 3.242399 |
| 1.26419 | 3.241092 |
| 1.27322 | 3.239807 |
| 1.28232 | 3.238542 |
| 1.29149 | 3.237298 |
| 1.30072 | 3.236074 |
| 1.31002 | 3.23487 |
| 1.31938 | 3.233686 |
| 1.32881 | 3.23252 |
| 1.33831 | 3.231373 |
| 1.34787 | 3.230245 |
| 1.35751 | 3.229135 |
| 1.36721 | 3.228042 |
| 1.37698 | 3.226967 |
| 1.38682 | 3.225909 |
| 1.39673 | 3.224868 |
| 1.40672 | 3.223843 |
| 1.41677 | 3.222834 |
| 1.4269 | 3.221841 |
| 1.43709 | 3.220864 |
| 1.44736 | 3.219902 |
| 1.45771 | 3.218955 |
| 1.46813 | 3.218023 |
| 1.47862 | 3.217105 |
| 1.48919 | 3.216201 |
| 1.49983 | 3.215312 |
| 1.51055 | 3.214436 |
| 1.52135 | 3.213573 |
| 1.53222 | 3.212724 |
| 1.54317 | 3.211888 |
| 1.5542 | 3.211065 |
| 1.56531 | 3.210254 |
| 1.5765 | 3.209455 |
| 1.58776 | 3.208669 |
| 1.59911 | 3.207894 |
| 1.61054 | 3.207131 |
| 1.62205 | 3.20638 |
| 1.63365 | 3.20564 |
| 1.64532 | 3.204911 |
| 1.65708 | 3.204192 |
| 1.66892 | 3.203485 |
| 1.68085 | 3.202788 |
| 1.69287 | 3.202101 |
| 1.70497 | 3.201425 |
| 1.71715 | 3.200758 |
| 1.72942 | 3.200101 |
| 1.74178 | 3.199454 |
| 1.75423 | 3.198817 |
| 1.76677 | 3.198188 |
| 1.7794 | 3.197569 |
| 1.79212 | 3.196959 |
| 1.80492 | 3.196357 |
| 1.81782 | 3.195764 |
| 1.83082 | 3.19518 |
| 1.8439 | 3.194604 |
| 1.85708 | 3.194036 |
| 1.87035 | 3.193477 |
| 1.88372 | 3.192925 |
| 1.89719 | 3.192381 |
| 1.91074 | 3.191845 |
| 1.9244 | 3.191316 |
| 1.93816 | 3.190795 |
| 1.95201 | 3.190281 |
| 1.96596 | 3.189774 |
| 1.98001 | 3.189275 |
| 1.99416 | 3.188782 |
| 2.00841 | 3.188296 |
| 2.02277 | 3.187816 |
| 2.03723 | 3.187344 |
| 2.05179 | 3.186877 |
| 2.06645 | 3.186417 |
| 2.08122 | 3.185963 |
| 2.09609 | 3.185515 |
| 2.11108 | 3.185074 |
| 2.12616 | 3.184638 |
| 2.14136 | 3.184208 |
| 2.15666 | 3.183783 |
| 2.17208 | 3.183365 |
| 2.1876 | 3.182951 |
| 2.20324 | 3.182543 |
| 2.21899 | 3.182141 |
| 2.23484 | 3.181743 |
| 2.25082 | 3.181351 |
| 2.2669 | 3.180964 |
| 2.28311 | 3.180581 |
| 2.29942 | 3.180204 |
| 2.31586 | 3.179831 |
| 2.33241 | 3.179463 |
| 2.34908 | 3.1791 |
| 2.36587 | 3.178741 |
| 2.38278 | 3.178386 |
| 2.39981 | 3.178036 |
| 2.41696 | 3.17769 |
| 2.43424 | 3.177348 |
| 2.45163 | 3.17701 |
| 2.46916 | 3.176676 |
| 2.4868 | 3.176347 |
| 2.50458 | 3.176021 |
| 2.52248 | 3.175699 |
| 2.54051 | 3.17538 |
| 2.55866 | 3.175065 |
| 2.57695 | 3.174754 |
| 2.59537 | 3.174447 |
| 2.61392 | 3.174142 |
| 2.6326 | 3.173842 |
| 2.65142 | 3.173544 |
| 2.67037 | 3.17325 |
| 2.68945 | 3.172958 |
| 2.70867 | 3.17267 |
| 2.72803 | 3.172385 |
| 2.74753 | 3.172103 |
| 2.76717 | 3.171824 |
| 2.78695 | 3.171548 |
| 2.80686 | 3.171274 |
| 2.82693 | 3.171004 |
| 2.84713 | 3.170736 |
| 2.86748 | 3.17047 |
| 2.88797 | 3.170207 |
| 2.90861 | 3.169947 |
| 2.9294 | 3.169689 |
| 2.95034 | 3.169433 |
| 2.97143 | 3.16918 |
| 2.99266 | 3.168929 |
| 3.01405 | 3.16868 |
| 3.03559 | 3.168433 |
| 3.05729 | 3.168189 |
| 3.07914 | 3.167946 |
| 3.10115 | 3.167706 |
| 3.12331 | 3.167467 |
| 3.14564 | 3.16723 |
| 3.16812 | 3.166995 |
| 3.19076 | 3.166762 |
| 3.21357 | 3.166531 |
| 3.23653 | 3.166301 |
| 3.25967 | 3.166073 |
| 3.28296 | 3.165847 |
| 3.30643 | 3.165622 |
| 3.33006 | 3.165399 |
| 3.35386 | 3.165177 |
| 3.37783 | 3.164956 |
| 3.40197 | 3.164737 |
| 3.42629 | 3.164519 |
| 3.45078 | 3.164302 |
| 3.47544 | 3.164087 |
| 3.50028 | 3.163872 |
| 3.5253 | 3.163659 |
| 3.55049 | 3.163447 |
| 3.57587 | 3.163236 |
| 3.60142 | 3.163026 |
| 3.62716 | 3.162816 |
| 3.65309 | 3.162608 |
| 3.6792 | 3.1624 |
| 3.70549 | 3.162194 |
| 3.73198 | 3.161988 |
| 3.75865 | 3.161782 |
| 3.78551 | 3.161578 |
| 3.81257 | 3.161374 |
| 3.83982 | 3.16117 |
| 3.86726 | 3.160967 |
| 3.8949 | 3.160765 |
| 3.92274 | 3.160562 |
| 3.95078 | 3.160361 |
| 3.97901 | 3.160159 |
| 4.00745 | 3.159958 |
| 4.03609 | 3.159758 |
| 4.06494 | 3.159557 |
| 4.09399 | 3.159357 |
| 4.12325 | 3.159156 |
| 4.15272 | 3.158956 |
| 4.1824 | 3.158756 |
| 4.2123 | 3.158556 |
| 4.2424 | 3.158355 |
| 4.27272 | 3.158155 |
| 4.30326 | 3.157955 |
| 4.33402 | 3.157754 |
| 4.36499 | 3.157553 |
| 4.39619 | 3.157352 |
| 4.42761 | 3.15715 |
| 4.45926 | 3.156948 |
| 4.49113 | 3.156746 |
| 4.52323 | 3.156543 |
| 4.55556 | 3.15634 |
| 4.58812 | 3.156136 |
| 4.62091 | 3.155932 |
| 4.65393 | 3.155727 |
| 4.6872 | 3.155521 |
| 4.7207 | 3.155315 |
| 4.75444 | 3.155108 |
| 4.78842 | 3.1549 |
| 4.82264 | 3.154691 |
| 4.85711 | 3.154481 |
| 4.89182 | 3.15427 |
| 4.92679 | 3.154058 |
| 4.962 | 3.153845 |
| 4.99746 | 3.153631 |
| 5.03318 | 3.153416 |
| 5.06915 | 3.1532 |
| 5.10538 | 3.152982 |
| 5.14187 | 3.152763 |
| 5.17862 | 3.152543 |
| 5.21564 | 3.152321 |
| 5.25291 | 3.152098 |
| 5.29046 | 3.151873 |
| 5.32827 | 3.151647 |
| 5.36635 | 3.151419 |
| 5.4047 | 3.15119 |
| 5.44333 | 3.150958 |
| 5.48224 | 3.150725 |
| 5.52142 | 3.15049 |
| 5.56088 | 3.150254 |
| 5.60063 | 3.150015 |
| 5.64066 | 3.149774 |
| 5.68097 | 3.149531 |
| 5.72157 | 3.149286 |
| 5.76247 | 3.149039 |
| 5.80365 | 3.14879 |
| 5.84513 | 3.148538 |
| 5.88691 | 3.148284 |
| 5.92898 | 3.148027 |
| 5.97136 | 3.147768 |
| 6.01404 | 3.147506 |
| 6.05702 | 3.147242 |
| 6.10031 | 3.146975 |
| 6.14391 | 3.146706 |
| 6.18782 | 3.146433 |
| 6.23205 | 3.146158 |
| 6.27659 | 3.145879 |
| 6.32145 | 3.145598 |
| 6.36663 | 3.145313 |
| 6.41213 | 3.145025 |
| 6.45796 | 3.144735 |
| 6.50412 | 3.14444 |
| 6.5506 | 3.144142 |
| 6.59742 | 3.143841 |
| 6.64457 | 3.143536 |
| 6.69206 | 3.143228 |
| 6.73989 | 3.142916 |
| 6.78807 | 3.1426 |
| 6.83658 | 3.14228 |
| 6.88544 | 3.141956 |
| 6.93465 | 3.141628 |
| 6.98422 | 3.141296 |
| 7.03414 | 3.14096 |
| 7.08441 | 3.140619 |
| 7.13504 | 3.140274 |
| 7.18604 | 3.139924 |
| 7.2374 | 3.13957 |
| 7.28913 | 3.139211 |
| 7.34122 | 3.138847 |
| 7.39369 | 3.138478 |
| 7.44654 | 3.138105 |
| 7.49976 | 3.137726 |
| 7.55336 | 3.137341 |
| 7.60734 | 3.136952 |
| 7.66172 | 3.136557 |
| 7.71647 | 3.136156 |
| 7.77163 | 3.13575 |
| 7.82717 | 3.135338 |
| 7.88311 | 3.13492 |
| 7.93946 | 3.134495 |
| 7.9962 | 3.134065 |
| 8.05335 | 3.133628 |
| 8.11091 | 3.133185 |
| 8.16888 | 3.132735 |
| 8.22726 | 3.132279 |
| 8.28607 | 3.131816 |
| 8.34529 | 3.131345 |
| 8.40493 | 3.130868 |
| 8.465 | 3.130383 |
| 8.5255 | 3.12989 |
| 8.58644 | 3.12939 |
| 8.64781 | 3.128882 |
| 8.70961 | 3.128367 |
| 8.77186 | 3.127843 |
| 8.83456 | 3.127311 |
| 8.8977 | 3.12677 |
| 8.96129 | 3.12622 |
| 9.02534 | 3.125662 |
| 9.08985 | 3.125095 |
| 9.15481 | 3.124519 |
| 9.22024 | 3.123933 |
| 9.28614 | 3.123337 |
| 9.35251 | 3.122732 |
| 9.41936 | 3.122117 |
| 9.48668 | 3.121491 |
| 9.55448 | 3.120855 |
| 9.62277 | 3.120208 |
| 9.69155 | 3.11955 |
| 9.76081 | 3.118881 |
| 9.83057 | 3.118201 |
| 9.90084 | 3.117509 |
| 9.9716 | 3.116805 |
| 10.0429 | 3.116089 |
| 10.1146 | 3.11536 |
| 10.1869 | 3.114618 |
| 10.2597 | 3.113864 |
| 10.3331 | 3.113096 |
| 10.4069 | 3.112314 |
| 10.4813 | 3.111518 |
| 10.5562 | 3.110709 |
| 10.6317 | 3.109884 |
| 10.7077 | 3.109045 |
| 10.7842 | 3.10819 |
| 10.8613 | 3.107319 |
| 10.9389 | 3.106433 |
| 11.0171 | 3.10553 |
| 11.0958 | 3.10461 |
| 11.1751 | 3.103673 |
| 11.255 | 3.102719 |
| 11.3354 | 3.101746 |
| 11.4164 | 3.100755 |
| 11.498 | 3.099745 |
| 11.5802 | 3.098715 |
| 11.663 | 3.097666 |
| 11.7463 | 3.096596 |
| 11.8303 | 3.095506 |
| 11.9148 | 3.094393 |
| 12 | 3.093259 |
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
- —
Critical analysis of experimental data from multiple sources.