Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(e) 0.7–12 µm; 350 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 350 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
- 3.17841
- Extinction coefficient k
- 0
- Permittivity ε1
- 10.1023
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0123871 µm⁻¹
- Group index ng
- 3.21433
- Group velocity dispersion
- 432.189 fs²/mm
- Dispersion parameter D
- -96.8006 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; 350 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-350K-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_bb29f2b35944/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-1998-350k-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_bb29f2b35944/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 | 4.13295051 |
| C2 | 4.89674401 |
| C3 | 0.15576712 |
| C4 | 2.10317249 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 350 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 | 3.508653 |
| 0.705003 | 3.501946 |
| 0.710042 | 3.495406 |
| 0.715117 | 3.489029 |
| 0.720228 | 3.482808 |
| 0.725375 | 3.476739 |
| 0.73056 | 3.470817 |
| 0.735781 | 3.465037 |
| 0.74104 | 3.459395 |
| 0.746336 | 3.453886 |
| 0.75167 | 3.448506 |
| 0.757043 | 3.443251 |
| 0.762453 | 3.438117 |
| 0.767903 | 3.433101 |
| 0.773391 | 3.428199 |
| 0.778919 | 3.423408 |
| 0.784486 | 3.418724 |
| 0.790093 | 3.414144 |
| 0.79574 | 3.409666 |
| 0.801427 | 3.405286 |
| 0.807155 | 3.401001 |
| 0.812924 | 3.39681 |
| 0.818734 | 3.392708 |
| 0.824585 | 3.388695 |
| 0.830479 | 3.384767 |
| 0.836414 | 3.380922 |
| 0.842392 | 3.377158 |
| 0.848413 | 3.373473 |
| 0.854477 | 3.369864 |
| 0.860584 | 3.366329 |
| 0.866735 | 3.362868 |
| 0.87293 | 3.359477 |
| 0.879169 | 3.356154 |
| 0.885452 | 3.352899 |
| 0.891781 | 3.34971 |
| 0.898154 | 3.346584 |
| 0.904574 | 3.34352 |
| 0.911039 | 3.340517 |
| 0.91755 | 3.337573 |
| 0.924108 | 3.334687 |
| 0.930713 | 3.331857 |
| 0.937365 | 3.329082 |
| 0.944064 | 3.326361 |
| 0.950812 | 3.323692 |
| 0.957607 | 3.321074 |
| 0.964451 | 3.318505 |
| 0.971345 | 3.315986 |
| 0.978287 | 3.313514 |
| 0.985279 | 3.311088 |
| 0.992321 | 3.308708 |
| 0.999413 | 3.306373 |
| 1.00656 | 3.30408 |
| 1.01375 | 3.30183 |
| 1.021 | 3.299622 |
| 1.02829 | 3.297454 |
| 1.03564 | 3.295325 |
| 1.04304 | 3.293235 |
| 1.0505 | 3.291184 |
| 1.05801 | 3.289169 |
| 1.06557 | 3.28719 |
| 1.07318 | 3.285247 |
| 1.08085 | 3.283338 |
| 1.08858 | 3.281464 |
| 1.09636 | 3.279622 |
| 1.1042 | 3.277814 |
| 1.11209 | 3.276037 |
| 1.12004 | 3.274291 |
| 1.12804 | 3.272576 |
| 1.1361 | 3.27089 |
| 1.14422 | 3.269234 |
| 1.1524 | 3.267607 |
| 1.16064 | 3.266007 |
| 1.16893 | 3.264435 |
| 1.17729 | 3.26289 |
| 1.1857 | 3.261372 |
| 1.19418 | 3.259879 |
| 1.20271 | 3.258412 |
| 1.21131 | 3.256969 |
| 1.21997 | 3.255551 |
| 1.22868 | 3.254157 |
| 1.23747 | 3.252786 |
| 1.24631 | 3.251438 |
| 1.25522 | 3.250112 |
| 1.26419 | 3.248809 |
| 1.27322 | 3.247527 |
| 1.28232 | 3.246266 |
| 1.29149 | 3.245026 |
| 1.30072 | 3.243807 |
| 1.31002 | 3.242607 |
| 1.31938 | 3.241427 |
| 1.32881 | 3.240267 |
| 1.33831 | 3.239125 |
| 1.34787 | 3.238002 |
| 1.35751 | 3.236897 |
| 1.36721 | 3.235809 |
| 1.37698 | 3.23474 |
| 1.38682 | 3.233687 |
| 1.39673 | 3.232651 |
| 1.40672 | 3.231632 |
| 1.41677 | 3.230629 |
| 1.4269 | 3.229642 |
| 1.43709 | 3.228671 |
| 1.44736 | 3.227715 |
| 1.45771 | 3.226774 |
| 1.46813 | 3.225847 |
| 1.47862 | 3.224936 |
| 1.48919 | 3.224038 |
| 1.49983 | 3.223155 |
| 1.51055 | 3.222285 |
| 1.52135 | 3.221429 |
| 1.53222 | 3.220586 |
| 1.54317 | 3.219756 |
| 1.5542 | 3.218939 |
| 1.56531 | 3.218135 |
| 1.5765 | 3.217342 |
| 1.58776 | 3.216562 |
| 1.59911 | 3.215794 |
| 1.61054 | 3.215037 |
| 1.62205 | 3.214292 |
| 1.63365 | 3.213558 |
| 1.64532 | 3.212836 |
| 1.65708 | 3.212124 |
| 1.66892 | 3.211423 |
| 1.68085 | 3.210732 |
| 1.69287 | 3.210052 |
| 1.70497 | 3.209381 |
| 1.71715 | 3.208721 |
| 1.72942 | 3.208071 |
| 1.74178 | 3.20743 |
| 1.75423 | 3.206798 |
| 1.76677 | 3.206176 |
| 1.7794 | 3.205563 |
| 1.79212 | 3.204959 |
| 1.80492 | 3.204363 |
| 1.81782 | 3.203777 |
| 1.83082 | 3.203199 |
| 1.8439 | 3.202629 |
| 1.85708 | 3.202067 |
| 1.87035 | 3.201513 |
| 1.88372 | 3.200968 |
| 1.89719 | 3.20043 |
| 1.91074 | 3.1999 |
| 1.9244 | 3.199377 |
| 1.93816 | 3.198862 |
| 1.95201 | 3.198353 |
| 1.96596 | 3.197852 |
| 1.98001 | 3.197358 |
| 1.99416 | 3.196871 |
| 2.00841 | 3.196391 |
| 2.02277 | 3.195917 |
| 2.03723 | 3.19545 |
| 2.05179 | 3.194989 |
| 2.06645 | 3.194535 |
| 2.08122 | 3.194086 |
| 2.09609 | 3.193644 |
| 2.11108 | 3.193208 |
| 2.12616 | 3.192777 |
| 2.14136 | 3.192353 |
| 2.15666 | 3.191934 |
| 2.17208 | 3.19152 |
| 2.1876 | 3.191112 |
| 2.20324 | 3.19071 |
| 2.21899 | 3.190312 |
| 2.23484 | 3.18992 |
| 2.25082 | 3.189533 |
| 2.2669 | 3.189151 |
| 2.28311 | 3.188774 |
| 2.29942 | 3.188402 |
| 2.31586 | 3.188034 |
| 2.33241 | 3.187671 |
| 2.34908 | 3.187312 |
| 2.36587 | 3.186958 |
| 2.38278 | 3.186609 |
| 2.39981 | 3.186263 |
| 2.41696 | 3.185922 |
| 2.43424 | 3.185585 |
| 2.45163 | 3.185253 |
| 2.46916 | 3.184924 |
| 2.4868 | 3.184599 |
| 2.50458 | 3.184278 |
| 2.52248 | 3.18396 |
| 2.54051 | 3.183647 |
| 2.55866 | 3.183337 |
| 2.57695 | 3.18303 |
| 2.59537 | 3.182727 |
| 2.61392 | 3.182427 |
| 2.6326 | 3.182131 |
| 2.65142 | 3.181838 |
| 2.67037 | 3.181549 |
| 2.68945 | 3.181262 |
| 2.70867 | 3.180978 |
| 2.72803 | 3.180698 |
| 2.74753 | 3.18042 |
| 2.76717 | 3.180146 |
| 2.78695 | 3.179874 |
| 2.80686 | 3.179605 |
| 2.82693 | 3.179339 |
| 2.84713 | 3.179075 |
| 2.86748 | 3.178814 |
| 2.88797 | 3.178556 |
| 2.90861 | 3.178299 |
| 2.9294 | 3.178046 |
| 2.95034 | 3.177795 |
| 2.97143 | 3.177546 |
| 2.99266 | 3.177299 |
| 3.01405 | 3.177055 |
| 3.03559 | 3.176812 |
| 3.05729 | 3.176572 |
| 3.07914 | 3.176334 |
| 3.10115 | 3.176098 |
| 3.12331 | 3.175863 |
| 3.14564 | 3.175631 |
| 3.16812 | 3.1754 |
| 3.19076 | 3.175172 |
| 3.21357 | 3.174945 |
| 3.23653 | 3.174719 |
| 3.25967 | 3.174495 |
| 3.28296 | 3.174273 |
| 3.30643 | 3.174053 |
| 3.33006 | 3.173834 |
| 3.35386 | 3.173616 |
| 3.37783 | 3.1734 |
| 3.40197 | 3.173185 |
| 3.42629 | 3.172971 |
| 3.45078 | 3.172759 |
| 3.47544 | 3.172548 |
| 3.50028 | 3.172338 |
| 3.5253 | 3.172129 |
| 3.55049 | 3.171921 |
| 3.57587 | 3.171714 |
| 3.60142 | 3.171508 |
| 3.62716 | 3.171303 |
| 3.65309 | 3.171099 |
| 3.6792 | 3.170896 |
| 3.70549 | 3.170694 |
| 3.73198 | 3.170492 |
| 3.75865 | 3.170291 |
| 3.78551 | 3.170091 |
| 3.81257 | 3.169891 |
| 3.83982 | 3.169692 |
| 3.86726 | 3.169494 |
| 3.8949 | 3.169296 |
| 3.92274 | 3.169098 |
| 3.95078 | 3.168901 |
| 3.97901 | 3.168705 |
| 4.00745 | 3.168508 |
| 4.03609 | 3.168312 |
| 4.06494 | 3.168116 |
| 4.09399 | 3.16792 |
| 4.12325 | 3.167725 |
| 4.15272 | 3.167529 |
| 4.1824 | 3.167334 |
| 4.2123 | 3.167138 |
| 4.2424 | 3.166943 |
| 4.27272 | 3.166747 |
| 4.30326 | 3.166552 |
| 4.33402 | 3.166356 |
| 4.36499 | 3.16616 |
| 4.39619 | 3.165964 |
| 4.42761 | 3.165767 |
| 4.45926 | 3.165571 |
| 4.49113 | 3.165373 |
| 4.52323 | 3.165176 |
| 4.55556 | 3.164978 |
| 4.58812 | 3.164779 |
| 4.62091 | 3.16458 |
| 4.65393 | 3.16438 |
| 4.6872 | 3.16418 |
| 4.7207 | 3.163979 |
| 4.75444 | 3.163777 |
| 4.78842 | 3.163575 |
| 4.82264 | 3.163371 |
| 4.85711 | 3.163167 |
| 4.89182 | 3.162962 |
| 4.92679 | 3.162756 |
| 4.962 | 3.162549 |
| 4.99746 | 3.162341 |
| 5.03318 | 3.162132 |
| 5.06915 | 3.161921 |
| 5.10538 | 3.16171 |
| 5.14187 | 3.161497 |
| 5.17862 | 3.161283 |
| 5.21564 | 3.161067 |
| 5.25291 | 3.16085 |
| 5.29046 | 3.160632 |
| 5.32827 | 3.160412 |
| 5.36635 | 3.160191 |
| 5.4047 | 3.159968 |
| 5.44333 | 3.159743 |
| 5.48224 | 3.159517 |
| 5.52142 | 3.159288 |
| 5.56088 | 3.159058 |
| 5.60063 | 3.158827 |
| 5.64066 | 3.158593 |
| 5.68097 | 3.158357 |
| 5.72157 | 3.158119 |
| 5.76247 | 3.157879 |
| 5.80365 | 3.157637 |
| 5.84513 | 3.157393 |
| 5.88691 | 3.157147 |
| 5.92898 | 3.156898 |
| 5.97136 | 3.156646 |
| 6.01404 | 3.156393 |
| 6.05702 | 3.156136 |
| 6.10031 | 3.155878 |
| 6.14391 | 3.155616 |
| 6.18782 | 3.155352 |
| 6.23205 | 3.155085 |
| 6.27659 | 3.154815 |
| 6.32145 | 3.154542 |
| 6.36663 | 3.154266 |
| 6.41213 | 3.153987 |
| 6.45796 | 3.153705 |
| 6.50412 | 3.15342 |
| 6.5506 | 3.153132 |
| 6.59742 | 3.15284 |
| 6.64457 | 3.152544 |
| 6.69206 | 3.152246 |
| 6.73989 | 3.151943 |
| 6.78807 | 3.151637 |
| 6.83658 | 3.151327 |
| 6.88544 | 3.151014 |
| 6.93465 | 3.150696 |
| 6.98422 | 3.150374 |
| 7.03414 | 3.150049 |
| 7.08441 | 3.149719 |
| 7.13504 | 3.149385 |
| 7.18604 | 3.149046 |
| 7.2374 | 3.148703 |
| 7.28913 | 3.148356 |
| 7.34122 | 3.148003 |
| 7.39369 | 3.147646 |
| 7.44654 | 3.147285 |
| 7.49976 | 3.146918 |
| 7.55336 | 3.146546 |
| 7.60734 | 3.146169 |
| 7.66172 | 3.145787 |
| 7.71647 | 3.145399 |
| 7.77163 | 3.145006 |
| 7.82717 | 3.144607 |
| 7.88311 | 3.144202 |
| 7.93946 | 3.143792 |
| 7.9962 | 3.143375 |
| 8.05335 | 3.142953 |
| 8.11091 | 3.142524 |
| 8.16888 | 3.142089 |
| 8.22726 | 3.141647 |
| 8.28607 | 3.141199 |
| 8.34529 | 3.140744 |
| 8.40493 | 3.140282 |
| 8.465 | 3.139813 |
| 8.5255 | 3.139337 |
| 8.58644 | 3.138853 |
| 8.64781 | 3.138362 |
| 8.70961 | 3.137863 |
| 8.77186 | 3.137357 |
| 8.83456 | 3.136842 |
| 8.8977 | 3.136319 |
| 8.96129 | 3.135788 |
| 9.02534 | 3.135248 |
| 9.08985 | 3.1347 |
| 9.15481 | 3.134142 |
| 9.22024 | 3.133576 |
| 9.28614 | 3.133 |
| 9.35251 | 3.132415 |
| 9.41936 | 3.13182 |
| 9.48668 | 3.131215 |
| 9.55448 | 3.1306 |
| 9.62277 | 3.129975 |
| 9.69155 | 3.129339 |
| 9.76081 | 3.128692 |
| 9.83057 | 3.128034 |
| 9.90084 | 3.127365 |
| 9.9716 | 3.126685 |
| 10.0429 | 3.125992 |
| 10.1146 | 3.125288 |
| 10.1869 | 3.124571 |
| 10.2597 | 3.123842 |
| 10.3331 | 3.1231 |
| 10.4069 | 3.122344 |
| 10.4813 | 3.121575 |
| 10.5562 | 3.120793 |
| 10.6317 | 3.119996 |
| 10.7077 | 3.119184 |
| 10.7842 | 3.118358 |
| 10.8613 | 3.117517 |
| 10.9389 | 3.11666 |
| 11.0171 | 3.115788 |
| 11.0958 | 3.114899 |
| 11.1751 | 3.113994 |
| 11.255 | 3.113071 |
| 11.3354 | 3.112131 |
| 11.4164 | 3.111174 |
| 11.498 | 3.110198 |
| 11.5802 | 3.109203 |
| 11.663 | 3.108189 |
| 11.7463 | 3.107156 |
| 11.8303 | 3.106102 |
| 11.9148 | 3.105027 |
| 12 | 3.103932 |
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.