Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(e) 0.7–12 µm; 300 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 300 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
- 3.17014
- Extinction coefficient k
- 0
- Permittivity ε1
- 10.0498
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0123072 µm⁻¹
- Group index ng
- 3.20583
- Group velocity dispersion
- 427.572 fs²/mm
- Dispersion parameter D
- -95.7665 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; 300 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-300K-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_59272c6ef865/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-1998-300k-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_59272c6ef865/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 | 3.69874418 |
| C2 | 5.27924444 |
| C3 | 0.14339365 |
| C4 | 2.09861247 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 300 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 | 3.487249 |
| 0.705003 | 3.481017 |
| 0.710042 | 3.474932 |
| 0.715117 | 3.468991 |
| 0.720228 | 3.463188 |
| 0.725375 | 3.45752 |
| 0.73056 | 3.451983 |
| 0.735781 | 3.446572 |
| 0.74104 | 3.441283 |
| 0.746336 | 3.436114 |
| 0.75167 | 3.43106 |
| 0.757043 | 3.426118 |
| 0.762453 | 3.421286 |
| 0.767903 | 3.416559 |
| 0.773391 | 3.411935 |
| 0.778919 | 3.407411 |
| 0.784486 | 3.402985 |
| 0.790093 | 3.398653 |
| 0.79574 | 3.394412 |
| 0.801427 | 3.390262 |
| 0.807155 | 3.386198 |
| 0.812924 | 3.382219 |
| 0.818734 | 3.378323 |
| 0.824585 | 3.374506 |
| 0.830479 | 3.370768 |
| 0.836414 | 3.367107 |
| 0.842392 | 3.363519 |
| 0.848413 | 3.360004 |
| 0.854477 | 3.356559 |
| 0.860584 | 3.353183 |
| 0.866735 | 3.349874 |
| 0.87293 | 3.34663 |
| 0.879169 | 3.34345 |
| 0.885452 | 3.340332 |
| 0.891781 | 3.337275 |
| 0.898154 | 3.334277 |
| 0.904574 | 3.331337 |
| 0.911039 | 3.328454 |
| 0.91755 | 3.325625 |
| 0.924108 | 3.32285 |
| 0.930713 | 3.320128 |
| 0.937365 | 3.317457 |
| 0.944064 | 3.314836 |
| 0.950812 | 3.312264 |
| 0.957607 | 3.30974 |
| 0.964451 | 3.307263 |
| 0.971345 | 3.304831 |
| 0.978287 | 3.302445 |
| 0.985279 | 3.300102 |
| 0.992321 | 3.297801 |
| 0.999413 | 3.295543 |
| 1.00656 | 3.293325 |
| 1.01375 | 3.291147 |
| 1.021 | 3.289009 |
| 1.02829 | 3.286908 |
| 1.03564 | 3.284845 |
| 1.04304 | 3.282819 |
| 1.0505 | 3.280829 |
| 1.05801 | 3.278874 |
| 1.06557 | 3.276953 |
| 1.07318 | 3.275066 |
| 1.08085 | 3.273211 |
| 1.08858 | 3.271389 |
| 1.09636 | 3.269599 |
| 1.1042 | 3.26784 |
| 1.11209 | 3.266111 |
| 1.12004 | 3.264412 |
| 1.12804 | 3.262741 |
| 1.1361 | 3.2611 |
| 1.14422 | 3.259486 |
| 1.1524 | 3.2579 |
| 1.16064 | 3.25634 |
| 1.16893 | 3.254807 |
| 1.17729 | 3.2533 |
| 1.1857 | 3.251818 |
| 1.19418 | 3.250361 |
| 1.20271 | 3.248928 |
| 1.21131 | 3.247519 |
| 1.21997 | 3.246133 |
| 1.22868 | 3.24477 |
| 1.23747 | 3.24343 |
| 1.24631 | 3.242111 |
| 1.25522 | 3.240815 |
| 1.26419 | 3.239539 |
| 1.27322 | 3.238285 |
| 1.28232 | 3.237051 |
| 1.29149 | 3.235837 |
| 1.30072 | 3.234642 |
| 1.31002 | 3.233467 |
| 1.31938 | 3.232311 |
| 1.32881 | 3.231173 |
| 1.33831 | 3.230054 |
| 1.34787 | 3.228952 |
| 1.35751 | 3.227868 |
| 1.36721 | 3.226801 |
| 1.37698 | 3.225752 |
| 1.38682 | 3.224719 |
| 1.39673 | 3.223702 |
| 1.40672 | 3.222701 |
| 1.41677 | 3.221716 |
| 1.4269 | 3.220746 |
| 1.43709 | 3.219792 |
| 1.44736 | 3.218852 |
| 1.45771 | 3.217927 |
| 1.46813 | 3.217017 |
| 1.47862 | 3.21612 |
| 1.48919 | 3.215238 |
| 1.49983 | 3.214369 |
| 1.51055 | 3.213513 |
| 1.52135 | 3.212671 |
| 1.53222 | 3.211841 |
| 1.54317 | 3.211024 |
| 1.5542 | 3.21022 |
| 1.56531 | 3.209427 |
| 1.5765 | 3.208647 |
| 1.58776 | 3.207879 |
| 1.59911 | 3.207122 |
| 1.61054 | 3.206376 |
| 1.62205 | 3.205642 |
| 1.63365 | 3.204919 |
| 1.64532 | 3.204206 |
| 1.65708 | 3.203505 |
| 1.66892 | 3.202813 |
| 1.68085 | 3.202132 |
| 1.69287 | 3.201461 |
| 1.70497 | 3.2008 |
| 1.71715 | 3.200148 |
| 1.72942 | 3.199506 |
| 1.74178 | 3.198874 |
| 1.75423 | 3.198251 |
| 1.76677 | 3.197636 |
| 1.7794 | 3.197031 |
| 1.79212 | 3.196435 |
| 1.80492 | 3.195847 |
| 1.81782 | 3.195267 |
| 1.83082 | 3.194696 |
| 1.8439 | 3.194133 |
| 1.85708 | 3.193578 |
| 1.87035 | 3.193031 |
| 1.88372 | 3.192492 |
| 1.89719 | 3.19196 |
| 1.91074 | 3.191436 |
| 1.9244 | 3.190919 |
| 1.93816 | 3.19041 |
| 1.95201 | 3.189907 |
| 1.96596 | 3.189412 |
| 1.98001 | 3.188923 |
| 1.99416 | 3.188441 |
| 2.00841 | 3.187966 |
| 2.02277 | 3.187497 |
| 2.03723 | 3.187035 |
| 2.05179 | 3.186579 |
| 2.06645 | 3.186129 |
| 2.08122 | 3.185686 |
| 2.09609 | 3.185248 |
| 2.11108 | 3.184816 |
| 2.12616 | 3.18439 |
| 2.14136 | 3.183969 |
| 2.15666 | 3.183555 |
| 2.17208 | 3.183145 |
| 2.1876 | 3.182741 |
| 2.20324 | 3.182342 |
| 2.21899 | 3.181949 |
| 2.23484 | 3.18156 |
| 2.25082 | 3.181177 |
| 2.2669 | 3.180798 |
| 2.28311 | 3.180424 |
| 2.29942 | 3.180055 |
| 2.31586 | 3.179691 |
| 2.33241 | 3.179331 |
| 2.34908 | 3.178976 |
| 2.36587 | 3.178625 |
| 2.38278 | 3.178278 |
| 2.39981 | 3.177936 |
| 2.41696 | 3.177598 |
| 2.43424 | 3.177263 |
| 2.45163 | 3.176933 |
| 2.46916 | 3.176607 |
| 2.4868 | 3.176285 |
| 2.50458 | 3.175966 |
| 2.52248 | 3.175651 |
| 2.54051 | 3.17534 |
| 2.55866 | 3.175033 |
| 2.57695 | 3.174728 |
| 2.59537 | 3.174428 |
| 2.61392 | 3.17413 |
| 2.6326 | 3.173836 |
| 2.65142 | 3.173546 |
| 2.67037 | 3.173258 |
| 2.68945 | 3.172974 |
| 2.70867 | 3.172692 |
| 2.72803 | 3.172414 |
| 2.74753 | 3.172138 |
| 2.76717 | 3.171865 |
| 2.78695 | 3.171595 |
| 2.80686 | 3.171328 |
| 2.82693 | 3.171064 |
| 2.84713 | 3.170802 |
| 2.86748 | 3.170542 |
| 2.88797 | 3.170286 |
| 2.90861 | 3.170031 |
| 2.9294 | 3.169779 |
| 2.95034 | 3.16953 |
| 2.97143 | 3.169282 |
| 2.99266 | 3.169037 |
| 3.01405 | 3.168794 |
| 3.03559 | 3.168553 |
| 3.05729 | 3.168314 |
| 3.07914 | 3.168078 |
| 3.10115 | 3.167843 |
| 3.12331 | 3.16761 |
| 3.14564 | 3.167379 |
| 3.16812 | 3.167149 |
| 3.19076 | 3.166922 |
| 3.21357 | 3.166696 |
| 3.23653 | 3.166472 |
| 3.25967 | 3.16625 |
| 3.28296 | 3.166029 |
| 3.30643 | 3.165809 |
| 3.33006 | 3.165591 |
| 3.35386 | 3.165375 |
| 3.37783 | 3.165159 |
| 3.40197 | 3.164946 |
| 3.42629 | 3.164733 |
| 3.45078 | 3.164522 |
| 3.47544 | 3.164311 |
| 3.50028 | 3.164102 |
| 3.5253 | 3.163894 |
| 3.55049 | 3.163688 |
| 3.57587 | 3.163482 |
| 3.60142 | 3.163277 |
| 3.62716 | 3.163073 |
| 3.65309 | 3.16287 |
| 3.6792 | 3.162667 |
| 3.70549 | 3.162466 |
| 3.73198 | 3.162265 |
| 3.75865 | 3.162065 |
| 3.78551 | 3.161866 |
| 3.81257 | 3.161667 |
| 3.83982 | 3.161468 |
| 3.86726 | 3.161271 |
| 3.8949 | 3.161073 |
| 3.92274 | 3.160877 |
| 3.95078 | 3.16068 |
| 3.97901 | 3.160484 |
| 4.00745 | 3.160288 |
| 4.03609 | 3.160093 |
| 4.06494 | 3.159898 |
| 4.09399 | 3.159702 |
| 4.12325 | 3.159507 |
| 4.15272 | 3.159313 |
| 4.1824 | 3.159118 |
| 4.2123 | 3.158923 |
| 4.2424 | 3.158728 |
| 4.27272 | 3.158533 |
| 4.30326 | 3.158338 |
| 4.33402 | 3.158143 |
| 4.36499 | 3.157947 |
| 4.39619 | 3.157752 |
| 4.42761 | 3.157556 |
| 4.45926 | 3.15736 |
| 4.49113 | 3.157163 |
| 4.52323 | 3.156966 |
| 4.55556 | 3.156768 |
| 4.58812 | 3.15657 |
| 4.62091 | 3.156371 |
| 4.65393 | 3.156172 |
| 4.6872 | 3.155972 |
| 4.7207 | 3.155772 |
| 4.75444 | 3.15557 |
| 4.78842 | 3.155368 |
| 4.82264 | 3.155165 |
| 4.85711 | 3.154961 |
| 4.89182 | 3.154757 |
| 4.92679 | 3.154551 |
| 4.962 | 3.154344 |
| 4.99746 | 3.154136 |
| 5.03318 | 3.153928 |
| 5.06915 | 3.153718 |
| 5.10538 | 3.153506 |
| 5.14187 | 3.153294 |
| 5.17862 | 3.15308 |
| 5.21564 | 3.152865 |
| 5.25291 | 3.152648 |
| 5.29046 | 3.15243 |
| 5.32827 | 3.152211 |
| 5.36635 | 3.151989 |
| 5.4047 | 3.151767 |
| 5.44333 | 3.151542 |
| 5.48224 | 3.151316 |
| 5.52142 | 3.151088 |
| 5.56088 | 3.150859 |
| 5.60063 | 3.150627 |
| 5.64066 | 3.150394 |
| 5.68097 | 3.150158 |
| 5.72157 | 3.14992 |
| 5.76247 | 3.149681 |
| 5.80365 | 3.149439 |
| 5.84513 | 3.149195 |
| 5.88691 | 3.148949 |
| 5.92898 | 3.1487 |
| 5.97136 | 3.148449 |
| 6.01404 | 3.148195 |
| 6.05702 | 3.147939 |
| 6.10031 | 3.14768 |
| 6.14391 | 3.147419 |
| 6.18782 | 3.147155 |
| 6.23205 | 3.146888 |
| 6.27659 | 3.146618 |
| 6.32145 | 3.146346 |
| 6.36663 | 3.14607 |
| 6.41213 | 3.145791 |
| 6.45796 | 3.145509 |
| 6.50412 | 3.145224 |
| 6.5506 | 3.144936 |
| 6.59742 | 3.144644 |
| 6.64457 | 3.144349 |
| 6.69206 | 3.14405 |
| 6.73989 | 3.143748 |
| 6.78807 | 3.143442 |
| 6.83658 | 3.143132 |
| 6.88544 | 3.142819 |
| 6.93465 | 3.142501 |
| 6.98422 | 3.14218 |
| 7.03414 | 3.141854 |
| 7.08441 | 3.141524 |
| 7.13504 | 3.14119 |
| 7.18604 | 3.140851 |
| 7.2374 | 3.140509 |
| 7.28913 | 3.140161 |
| 7.34122 | 3.139809 |
| 7.39369 | 3.139452 |
| 7.44654 | 3.13909 |
| 7.49976 | 3.138723 |
| 7.55336 | 3.138351 |
| 7.60734 | 3.137974 |
| 7.66172 | 3.137592 |
| 7.71647 | 3.137204 |
| 7.77163 | 3.136811 |
| 7.82717 | 3.136412 |
| 7.88311 | 3.136008 |
| 7.93946 | 3.135597 |
| 7.9962 | 3.135181 |
| 8.05335 | 3.134758 |
| 8.11091 | 3.13433 |
| 8.16888 | 3.133894 |
| 8.22726 | 3.133453 |
| 8.28607 | 3.133004 |
| 8.34529 | 3.132549 |
| 8.40493 | 3.132087 |
| 8.465 | 3.131618 |
| 8.5255 | 3.131142 |
| 8.58644 | 3.130658 |
| 8.64781 | 3.130167 |
| 8.70961 | 3.129668 |
| 8.77186 | 3.129161 |
| 8.83456 | 3.128647 |
| 8.8977 | 3.128124 |
| 8.96129 | 3.127592 |
| 9.02534 | 3.127052 |
| 9.08985 | 3.126504 |
| 9.15481 | 3.125946 |
| 9.22024 | 3.12538 |
| 9.28614 | 3.124804 |
| 9.35251 | 3.124218 |
| 9.41936 | 3.123623 |
| 9.48668 | 3.123018 |
| 9.55448 | 3.122403 |
| 9.62277 | 3.121778 |
| 9.69155 | 3.121141 |
| 9.76081 | 3.120495 |
| 9.83057 | 3.119837 |
| 9.90084 | 3.119167 |
| 9.9716 | 3.118487 |
| 10.0429 | 3.117794 |
| 10.1146 | 3.117089 |
| 10.1869 | 3.116372 |
| 10.2597 | 3.115643 |
| 10.3331 | 3.1149 |
| 10.4069 | 3.114145 |
| 10.4813 | 3.113375 |
| 10.5562 | 3.112592 |
| 10.6317 | 3.111795 |
| 10.7077 | 3.110984 |
| 10.7842 | 3.110157 |
| 10.8613 | 3.109316 |
| 10.9389 | 3.108459 |
| 11.0171 | 3.107586 |
| 11.0958 | 3.106697 |
| 11.1751 | 3.105791 |
| 11.255 | 3.104868 |
| 11.3354 | 3.103928 |
| 11.4164 | 3.10297 |
| 11.498 | 3.101994 |
| 11.5802 | 3.100999 |
| 11.663 | 3.099984 |
| 11.7463 | 3.09895 |
| 11.8303 | 3.097896 |
| 11.9148 | 3.096821 |
| 12 | 3.095725 |
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.