Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(e) 0.7–12 µm; 400 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 400 K
- Optical axis
- e
- Licence
- CC0-1.0
Uniaxial crystal, axes: oe
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 3.18803
- Extinction coefficient k
- 0
- Permittivity ε1
- 10.1635
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0126276 µm⁻¹
- Group index ng
- 3.22465
- Group velocity dispersion
- 443.885 fs²/mm
- Dispersion parameter D
- -99.4203 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(e) 0.7–12 µm; 400 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-400K-e", 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_1a7e5d50e2c7/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-1998-400k-e).
# ... 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_1a7e5d50e2c7/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 | 4.0904278 |
| C2 | 4.99794548 |
| C3 | 0.15680542 |
| C4 | 2.09884054 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 400 K
- direction
- e
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 | 3.526943 |
| 0.705003 | 3.520044 |
| 0.710042 | 3.513319 |
| 0.715117 | 3.506761 |
| 0.720228 | 3.500365 |
| 0.725375 | 3.494126 |
| 0.73056 | 3.488038 |
| 0.735781 | 3.482096 |
| 0.74104 | 3.476296 |
| 0.746336 | 3.470633 |
| 0.75167 | 3.465104 |
| 0.757043 | 3.459703 |
| 0.762453 | 3.454428 |
| 0.767903 | 3.449273 |
| 0.773391 | 3.444236 |
| 0.778919 | 3.439313 |
| 0.784486 | 3.434501 |
| 0.790093 | 3.429796 |
| 0.79574 | 3.425196 |
| 0.801427 | 3.420696 |
| 0.807155 | 3.416296 |
| 0.812924 | 3.411991 |
| 0.818734 | 3.407778 |
| 0.824585 | 3.403656 |
| 0.830479 | 3.399623 |
| 0.836414 | 3.395674 |
| 0.842392 | 3.391809 |
| 0.848413 | 3.388025 |
| 0.854477 | 3.384319 |
| 0.860584 | 3.38069 |
| 0.866735 | 3.377136 |
| 0.87293 | 3.373655 |
| 0.879169 | 3.370244 |
| 0.885452 | 3.366903 |
| 0.891781 | 3.363628 |
| 0.898154 | 3.36042 |
| 0.904574 | 3.357275 |
| 0.911039 | 3.354193 |
| 0.91755 | 3.351171 |
| 0.924108 | 3.348209 |
| 0.930713 | 3.345305 |
| 0.937365 | 3.342457 |
| 0.944064 | 3.339664 |
| 0.950812 | 3.336925 |
| 0.957607 | 3.334238 |
| 0.964451 | 3.331603 |
| 0.971345 | 3.329017 |
| 0.978287 | 3.326481 |
| 0.985279 | 3.323992 |
| 0.992321 | 3.32155 |
| 0.999413 | 3.319154 |
| 1.00656 | 3.316802 |
| 1.01375 | 3.314494 |
| 1.021 | 3.312228 |
| 1.02829 | 3.310004 |
| 1.03564 | 3.30782 |
| 1.04304 | 3.305677 |
| 1.0505 | 3.303572 |
| 1.05801 | 3.301505 |
| 1.06557 | 3.299476 |
| 1.07318 | 3.297482 |
| 1.08085 | 3.295525 |
| 1.08858 | 3.293602 |
| 1.09636 | 3.291714 |
| 1.1042 | 3.289859 |
| 1.11209 | 3.288036 |
| 1.12004 | 3.286246 |
| 1.12804 | 3.284487 |
| 1.1361 | 3.282758 |
| 1.14422 | 3.28106 |
| 1.1524 | 3.279391 |
| 1.16064 | 3.277751 |
| 1.16893 | 3.276139 |
| 1.17729 | 3.274555 |
| 1.1857 | 3.272998 |
| 1.19418 | 3.271467 |
| 1.20271 | 3.269962 |
| 1.21131 | 3.268483 |
| 1.21997 | 3.267029 |
| 1.22868 | 3.2656 |
| 1.23747 | 3.264194 |
| 1.24631 | 3.262812 |
| 1.25522 | 3.261453 |
| 1.26419 | 3.260117 |
| 1.27322 | 3.258803 |
| 1.28232 | 3.25751 |
| 1.29149 | 3.256239 |
| 1.30072 | 3.254989 |
| 1.31002 | 3.25376 |
| 1.31938 | 3.25255 |
| 1.32881 | 3.25136 |
| 1.33831 | 3.25019 |
| 1.34787 | 3.249039 |
| 1.35751 | 3.247906 |
| 1.36721 | 3.246792 |
| 1.37698 | 3.245695 |
| 1.38682 | 3.244616 |
| 1.39673 | 3.243555 |
| 1.40672 | 3.24251 |
| 1.41677 | 3.241482 |
| 1.4269 | 3.240471 |
| 1.43709 | 3.239475 |
| 1.44736 | 3.238495 |
| 1.45771 | 3.237531 |
| 1.46813 | 3.236582 |
| 1.47862 | 3.235648 |
| 1.48919 | 3.234728 |
| 1.49983 | 3.233823 |
| 1.51055 | 3.232932 |
| 1.52135 | 3.232054 |
| 1.53222 | 3.231191 |
| 1.54317 | 3.23034 |
| 1.5542 | 3.229503 |
| 1.56531 | 3.228679 |
| 1.5765 | 3.227867 |
| 1.58776 | 3.227068 |
| 1.59911 | 3.226281 |
| 1.61054 | 3.225506 |
| 1.62205 | 3.224742 |
| 1.63365 | 3.223991 |
| 1.64532 | 3.22325 |
| 1.65708 | 3.222521 |
| 1.66892 | 3.221803 |
| 1.68085 | 3.221095 |
| 1.69287 | 3.220399 |
| 1.70497 | 3.219712 |
| 1.71715 | 3.219036 |
| 1.72942 | 3.218369 |
| 1.74178 | 3.217713 |
| 1.75423 | 3.217066 |
| 1.76677 | 3.216429 |
| 1.7794 | 3.215801 |
| 1.79212 | 3.215183 |
| 1.80492 | 3.214573 |
| 1.81782 | 3.213972 |
| 1.83082 | 3.21338 |
| 1.8439 | 3.212797 |
| 1.85708 | 3.212222 |
| 1.87035 | 3.211655 |
| 1.88372 | 3.211096 |
| 1.89719 | 3.210545 |
| 1.91074 | 3.210002 |
| 1.9244 | 3.209467 |
| 1.93816 | 3.20894 |
| 1.95201 | 3.20842 |
| 1.96596 | 3.207907 |
| 1.98001 | 3.207401 |
| 1.99416 | 3.206902 |
| 2.00841 | 3.206411 |
| 2.02277 | 3.205926 |
| 2.03723 | 3.205448 |
| 2.05179 | 3.204976 |
| 2.06645 | 3.204511 |
| 2.08122 | 3.204052 |
| 2.09609 | 3.2036 |
| 2.11108 | 3.203154 |
| 2.12616 | 3.202713 |
| 2.14136 | 3.202279 |
| 2.15666 | 3.20185 |
| 2.17208 | 3.201427 |
| 2.1876 | 3.20101 |
| 2.20324 | 3.200598 |
| 2.21899 | 3.200192 |
| 2.23484 | 3.199791 |
| 2.25082 | 3.199395 |
| 2.2669 | 3.199004 |
| 2.28311 | 3.198618 |
| 2.29942 | 3.198237 |
| 2.31586 | 3.197862 |
| 2.33241 | 3.19749 |
| 2.34908 | 3.197124 |
| 2.36587 | 3.196762 |
| 2.38278 | 3.196405 |
| 2.39981 | 3.196052 |
| 2.41696 | 3.195703 |
| 2.43424 | 3.195359 |
| 2.45163 | 3.195019 |
| 2.46916 | 3.194683 |
| 2.4868 | 3.194351 |
| 2.50458 | 3.194023 |
| 2.52248 | 3.193698 |
| 2.54051 | 3.193378 |
| 2.55866 | 3.193061 |
| 2.57695 | 3.192748 |
| 2.59537 | 3.192439 |
| 2.61392 | 3.192133 |
| 2.6326 | 3.191831 |
| 2.65142 | 3.191531 |
| 2.67037 | 3.191236 |
| 2.68945 | 3.190943 |
| 2.70867 | 3.190654 |
| 2.72803 | 3.190368 |
| 2.74753 | 3.190084 |
| 2.76717 | 3.189804 |
| 2.78695 | 3.189527 |
| 2.80686 | 3.189253 |
| 2.82693 | 3.188981 |
| 2.84713 | 3.188712 |
| 2.86748 | 3.188446 |
| 2.88797 | 3.188182 |
| 2.90861 | 3.187921 |
| 2.9294 | 3.187663 |
| 2.95034 | 3.187407 |
| 2.97143 | 3.187153 |
| 2.99266 | 3.186902 |
| 3.01405 | 3.186653 |
| 3.03559 | 3.186406 |
| 3.05729 | 3.186161 |
| 3.07914 | 3.185919 |
| 3.10115 | 3.185678 |
| 3.12331 | 3.18544 |
| 3.14564 | 3.185203 |
| 3.16812 | 3.184968 |
| 3.19076 | 3.184736 |
| 3.21357 | 3.184505 |
| 3.23653 | 3.184275 |
| 3.25967 | 3.184048 |
| 3.28296 | 3.183822 |
| 3.30643 | 3.183598 |
| 3.33006 | 3.183375 |
| 3.35386 | 3.183154 |
| 3.37783 | 3.182934 |
| 3.40197 | 3.182716 |
| 3.42629 | 3.182498 |
| 3.45078 | 3.182283 |
| 3.47544 | 3.182068 |
| 3.50028 | 3.181855 |
| 3.5253 | 3.181643 |
| 3.55049 | 3.181432 |
| 3.57587 | 3.181222 |
| 3.60142 | 3.181013 |
| 3.62716 | 3.180806 |
| 3.65309 | 3.180599 |
| 3.6792 | 3.180393 |
| 3.70549 | 3.180188 |
| 3.73198 | 3.179983 |
| 3.75865 | 3.17978 |
| 3.78551 | 3.179577 |
| 3.81257 | 3.179375 |
| 3.83982 | 3.179173 |
| 3.86726 | 3.178972 |
| 3.8949 | 3.178772 |
| 3.92274 | 3.178572 |
| 3.95078 | 3.178372 |
| 3.97901 | 3.178173 |
| 4.00745 | 3.177974 |
| 4.03609 | 3.177776 |
| 4.06494 | 3.177578 |
| 4.09399 | 3.17738 |
| 4.12325 | 3.177182 |
| 4.15272 | 3.176985 |
| 4.1824 | 3.176788 |
| 4.2123 | 3.17659 |
| 4.2424 | 3.176393 |
| 4.27272 | 3.176195 |
| 4.30326 | 3.175998 |
| 4.33402 | 3.175801 |
| 4.36499 | 3.175603 |
| 4.39619 | 3.175405 |
| 4.42761 | 3.175207 |
| 4.45926 | 3.175008 |
| 4.49113 | 3.17481 |
| 4.52323 | 3.17461 |
| 4.55556 | 3.174411 |
| 4.58812 | 3.174211 |
| 4.62091 | 3.17401 |
| 4.65393 | 3.173809 |
| 4.6872 | 3.173608 |
| 4.7207 | 3.173405 |
| 4.75444 | 3.173202 |
| 4.78842 | 3.172998 |
| 4.82264 | 3.172794 |
| 4.85711 | 3.172589 |
| 4.89182 | 3.172382 |
| 4.92679 | 3.172175 |
| 4.962 | 3.171967 |
| 4.99746 | 3.171758 |
| 5.03318 | 3.171548 |
| 5.06915 | 3.171336 |
| 5.10538 | 3.171124 |
| 5.14187 | 3.17091 |
| 5.17862 | 3.170695 |
| 5.21564 | 3.170479 |
| 5.25291 | 3.170261 |
| 5.29046 | 3.170042 |
| 5.32827 | 3.169821 |
| 5.36635 | 3.169599 |
| 5.4047 | 3.169376 |
| 5.44333 | 3.16915 |
| 5.48224 | 3.168923 |
| 5.52142 | 3.168695 |
| 5.56088 | 3.168464 |
| 5.60063 | 3.168232 |
| 5.64066 | 3.167998 |
| 5.68097 | 3.167761 |
| 5.72157 | 3.167523 |
| 5.76247 | 3.167283 |
| 5.80365 | 3.167041 |
| 5.84513 | 3.166796 |
| 5.88691 | 3.166549 |
| 5.92898 | 3.1663 |
| 5.97136 | 3.166049 |
| 6.01404 | 3.165795 |
| 6.05702 | 3.165538 |
| 6.10031 | 3.16528 |
| 6.14391 | 3.165018 |
| 6.18782 | 3.164754 |
| 6.23205 | 3.164487 |
| 6.27659 | 3.164217 |
| 6.32145 | 3.163944 |
| 6.36663 | 3.163668 |
| 6.41213 | 3.16339 |
| 6.45796 | 3.163108 |
| 6.50412 | 3.162823 |
| 6.5506 | 3.162535 |
| 6.59742 | 3.162243 |
| 6.64457 | 3.161948 |
| 6.69206 | 3.16165 |
| 6.73989 | 3.161348 |
| 6.78807 | 3.161042 |
| 6.83658 | 3.160732 |
| 6.88544 | 3.160419 |
| 6.93465 | 3.160102 |
| 6.98422 | 3.159781 |
| 7.03414 | 3.159456 |
| 7.08441 | 3.159127 |
| 7.13504 | 3.158793 |
| 7.18604 | 3.158455 |
| 7.2374 | 3.158113 |
| 7.28913 | 3.157766 |
| 7.34122 | 3.157415 |
| 7.39369 | 3.157059 |
| 7.44654 | 3.156698 |
| 7.49976 | 3.156332 |
| 7.55336 | 3.155961 |
| 7.60734 | 3.155585 |
| 7.66172 | 3.155204 |
| 7.71647 | 3.154817 |
| 7.77163 | 3.154425 |
| 7.82717 | 3.154028 |
| 7.88311 | 3.153624 |
| 7.93946 | 3.153215 |
| 7.9962 | 3.1528 |
| 8.05335 | 3.152379 |
| 8.11091 | 3.151951 |
| 8.16888 | 3.151518 |
| 8.22726 | 3.151078 |
| 8.28607 | 3.150631 |
| 8.34529 | 3.150177 |
| 8.40493 | 3.149717 |
| 8.465 | 3.14925 |
| 8.5255 | 3.148775 |
| 8.58644 | 3.148293 |
| 8.64781 | 3.147804 |
| 8.70961 | 3.147307 |
| 8.77186 | 3.146802 |
| 8.83456 | 3.146289 |
| 8.8977 | 3.145768 |
| 8.96129 | 3.145239 |
| 9.02534 | 3.144702 |
| 9.08985 | 3.144155 |
| 9.15481 | 3.1436 |
| 9.22024 | 3.143036 |
| 9.28614 | 3.142462 |
| 9.35251 | 3.14188 |
| 9.41936 | 3.141287 |
| 9.48668 | 3.140685 |
| 9.55448 | 3.140072 |
| 9.62277 | 3.13945 |
| 9.69155 | 3.138816 |
| 9.76081 | 3.138172 |
| 9.83057 | 3.137517 |
| 9.90084 | 3.136851 |
| 9.9716 | 3.136174 |
| 10.0429 | 3.135484 |
| 10.1146 | 3.134783 |
| 10.1869 | 3.134069 |
| 10.2597 | 3.133343 |
| 10.3331 | 3.132604 |
| 10.4069 | 3.131852 |
| 10.4813 | 3.131087 |
| 10.5562 | 3.130308 |
| 10.6317 | 3.129514 |
| 10.7077 | 3.128707 |
| 10.7842 | 3.127884 |
| 10.8613 | 3.127047 |
| 10.9389 | 3.126194 |
| 11.0171 | 3.125326 |
| 11.0958 | 3.124441 |
| 11.1751 | 3.12354 |
| 11.255 | 3.122622 |
| 11.3354 | 3.121686 |
| 11.4164 | 3.120733 |
| 11.498 | 3.119762 |
| 11.5802 | 3.118772 |
| 11.663 | 3.117763 |
| 11.7463 | 3.116734 |
| 11.8303 | 3.115685 |
| 11.9148 | 3.114616 |
| 12 | 3.113526 |
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.