Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(e) 0.7–12 µm; 500 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 500 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
- 3.21183
- Extinction coefficient k
- 0
- Permittivity ε1
- 10.3158
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0131674 µm⁻¹
- Group index ng
- 3.25001
- Group velocity dispersion
- 470.194 fs²/mm
- Dispersion parameter D
- -105.313 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; 500 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-500K-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_7e31cae1ac03/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-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_7e31cae1ac03/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 | 4.19415933 |
| C2 | 5.04078045 |
| C3 | 0.16466963 |
| C4 | 2.09668743 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 500 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 | 3.575646 |
| 0.705003 | 3.56809 |
| 0.710042 | 3.56073 |
| 0.715117 | 3.553559 |
| 0.720228 | 3.54657 |
| 0.725375 | 3.539757 |
| 0.73056 | 3.533115 |
| 0.735781 | 3.526637 |
| 0.74104 | 3.520318 |
| 0.746336 | 3.514153 |
| 0.75167 | 3.508137 |
| 0.757043 | 3.502265 |
| 0.762453 | 3.496533 |
| 0.767903 | 3.490936 |
| 0.773391 | 3.48547 |
| 0.778919 | 3.48013 |
| 0.784486 | 3.474914 |
| 0.790093 | 3.469817 |
| 0.79574 | 3.464836 |
| 0.801427 | 3.459967 |
| 0.807155 | 3.455208 |
| 0.812924 | 3.450554 |
| 0.818734 | 3.446003 |
| 0.824585 | 3.441552 |
| 0.830479 | 3.437198 |
| 0.836414 | 3.432938 |
| 0.842392 | 3.42877 |
| 0.848413 | 3.424691 |
| 0.854477 | 3.420698 |
| 0.860584 | 3.41679 |
| 0.866735 | 3.412965 |
| 0.87293 | 3.409219 |
| 0.879169 | 3.40555 |
| 0.885452 | 3.401958 |
| 0.891781 | 3.398439 |
| 0.898154 | 3.394992 |
| 0.904574 | 3.391615 |
| 0.911039 | 3.388306 |
| 0.91755 | 3.385063 |
| 0.924108 | 3.381886 |
| 0.930713 | 3.378771 |
| 0.937365 | 3.375718 |
| 0.944064 | 3.372725 |
| 0.950812 | 3.369791 |
| 0.957607 | 3.366914 |
| 0.964451 | 3.364092 |
| 0.971345 | 3.361325 |
| 0.978287 | 3.358611 |
| 0.985279 | 3.35595 |
| 0.992321 | 3.353338 |
| 0.999413 | 3.350776 |
| 1.00656 | 3.348263 |
| 1.01375 | 3.345797 |
| 1.021 | 3.343377 |
| 1.02829 | 3.341001 |
| 1.03564 | 3.33867 |
| 1.04304 | 3.336382 |
| 1.0505 | 3.334137 |
| 1.05801 | 3.331932 |
| 1.06557 | 3.329767 |
| 1.07318 | 3.327642 |
| 1.08085 | 3.325555 |
| 1.08858 | 3.323506 |
| 1.09636 | 3.321494 |
| 1.1042 | 3.319518 |
| 1.11209 | 3.317577 |
| 1.12004 | 3.31567 |
| 1.12804 | 3.313798 |
| 1.1361 | 3.311958 |
| 1.14422 | 3.310151 |
| 1.1524 | 3.308375 |
| 1.16064 | 3.306631 |
| 1.16893 | 3.304916 |
| 1.17729 | 3.303232 |
| 1.1857 | 3.301577 |
| 1.19418 | 3.29995 |
| 1.20271 | 3.298351 |
| 1.21131 | 3.296779 |
| 1.21997 | 3.295235 |
| 1.22868 | 3.293716 |
| 1.23747 | 3.292224 |
| 1.24631 | 3.290756 |
| 1.25522 | 3.289314 |
| 1.26419 | 3.287895 |
| 1.27322 | 3.286501 |
| 1.28232 | 3.285129 |
| 1.29149 | 3.283781 |
| 1.30072 | 3.282455 |
| 1.31002 | 3.281151 |
| 1.31938 | 3.279868 |
| 1.32881 | 3.278607 |
| 1.33831 | 3.277366 |
| 1.34787 | 3.276146 |
| 1.35751 | 3.274945 |
| 1.36721 | 3.273765 |
| 1.37698 | 3.272603 |
| 1.38682 | 3.27146 |
| 1.39673 | 3.270336 |
| 1.40672 | 3.26923 |
| 1.41677 | 3.268141 |
| 1.4269 | 3.26707 |
| 1.43709 | 3.266016 |
| 1.44736 | 3.264979 |
| 1.45771 | 3.263959 |
| 1.46813 | 3.262954 |
| 1.47862 | 3.261966 |
| 1.48919 | 3.260993 |
| 1.49983 | 3.260035 |
| 1.51055 | 3.259093 |
| 1.52135 | 3.258165 |
| 1.53222 | 3.257252 |
| 1.54317 | 3.256353 |
| 1.5542 | 3.255468 |
| 1.56531 | 3.254597 |
| 1.5765 | 3.253739 |
| 1.58776 | 3.252894 |
| 1.59911 | 3.252063 |
| 1.61054 | 3.251244 |
| 1.62205 | 3.250437 |
| 1.63365 | 3.249643 |
| 1.64532 | 3.248861 |
| 1.65708 | 3.248091 |
| 1.66892 | 3.247333 |
| 1.68085 | 3.246586 |
| 1.69287 | 3.24585 |
| 1.70497 | 3.245126 |
| 1.71715 | 3.244412 |
| 1.72942 | 3.243709 |
| 1.74178 | 3.243016 |
| 1.75423 | 3.242334 |
| 1.76677 | 3.241662 |
| 1.7794 | 3.241 |
| 1.79212 | 3.240347 |
| 1.80492 | 3.239704 |
| 1.81782 | 3.239071 |
| 1.83082 | 3.238447 |
| 1.8439 | 3.237832 |
| 1.85708 | 3.237225 |
| 1.87035 | 3.236628 |
| 1.88372 | 3.236039 |
| 1.89719 | 3.235459 |
| 1.91074 | 3.234887 |
| 1.9244 | 3.234323 |
| 1.93816 | 3.233768 |
| 1.95201 | 3.23322 |
| 1.96596 | 3.23268 |
| 1.98001 | 3.232147 |
| 1.99416 | 3.231622 |
| 2.00841 | 3.231105 |
| 2.02277 | 3.230595 |
| 2.03723 | 3.230091 |
| 2.05179 | 3.229595 |
| 2.06645 | 3.229106 |
| 2.08122 | 3.228623 |
| 2.09609 | 3.228147 |
| 2.11108 | 3.227678 |
| 2.12616 | 3.227215 |
| 2.14136 | 3.226758 |
| 2.15666 | 3.226307 |
| 2.17208 | 3.225863 |
| 2.1876 | 3.225424 |
| 2.20324 | 3.224992 |
| 2.21899 | 3.224565 |
| 2.23484 | 3.224143 |
| 2.25082 | 3.223728 |
| 2.2669 | 3.223317 |
| 2.28311 | 3.222912 |
| 2.29942 | 3.222512 |
| 2.31586 | 3.222118 |
| 2.33241 | 3.221728 |
| 2.34908 | 3.221344 |
| 2.36587 | 3.220964 |
| 2.38278 | 3.220589 |
| 2.39981 | 3.220219 |
| 2.41696 | 3.219853 |
| 2.43424 | 3.219492 |
| 2.45163 | 3.219136 |
| 2.46916 | 3.218784 |
| 2.4868 | 3.218436 |
| 2.50458 | 3.218092 |
| 2.52248 | 3.217752 |
| 2.54051 | 3.217417 |
| 2.55866 | 3.217085 |
| 2.57695 | 3.216758 |
| 2.59537 | 3.216434 |
| 2.61392 | 3.216114 |
| 2.6326 | 3.215797 |
| 2.65142 | 3.215484 |
| 2.67037 | 3.215175 |
| 2.68945 | 3.214869 |
| 2.70867 | 3.214567 |
| 2.72803 | 3.214268 |
| 2.74753 | 3.213972 |
| 2.76717 | 3.213679 |
| 2.78695 | 3.21339 |
| 2.80686 | 3.213103 |
| 2.82693 | 3.212819 |
| 2.84713 | 3.212539 |
| 2.86748 | 3.212261 |
| 2.88797 | 3.211986 |
| 2.90861 | 3.211714 |
| 2.9294 | 3.211445 |
| 2.95034 | 3.211178 |
| 2.97143 | 3.210913 |
| 2.99266 | 3.210652 |
| 3.01405 | 3.210392 |
| 3.03559 | 3.210135 |
| 3.05729 | 3.209881 |
| 3.07914 | 3.209628 |
| 3.10115 | 3.209378 |
| 3.12331 | 3.20913 |
| 3.14564 | 3.208884 |
| 3.16812 | 3.20864 |
| 3.19076 | 3.208399 |
| 3.21357 | 3.208159 |
| 3.23653 | 3.207921 |
| 3.25967 | 3.207685 |
| 3.28296 | 3.20745 |
| 3.30643 | 3.207218 |
| 3.33006 | 3.206987 |
| 3.35386 | 3.206758 |
| 3.37783 | 3.20653 |
| 3.40197 | 3.206304 |
| 3.42629 | 3.206079 |
| 3.45078 | 3.205856 |
| 3.47544 | 3.205634 |
| 3.50028 | 3.205413 |
| 3.5253 | 3.205194 |
| 3.55049 | 3.204976 |
| 3.57587 | 3.20476 |
| 3.60142 | 3.204544 |
| 3.62716 | 3.204329 |
| 3.65309 | 3.204116 |
| 3.6792 | 3.203904 |
| 3.70549 | 3.203692 |
| 3.73198 | 3.203482 |
| 3.75865 | 3.203272 |
| 3.78551 | 3.203063 |
| 3.81257 | 3.202855 |
| 3.83982 | 3.202648 |
| 3.86726 | 3.202441 |
| 3.8949 | 3.202235 |
| 3.92274 | 3.20203 |
| 3.95078 | 3.201825 |
| 3.97901 | 3.20162 |
| 4.00745 | 3.201417 |
| 4.03609 | 3.201213 |
| 4.06494 | 3.20101 |
| 4.09399 | 3.200807 |
| 4.12325 | 3.200605 |
| 4.15272 | 3.200403 |
| 4.1824 | 3.200201 |
| 4.2123 | 3.199999 |
| 4.2424 | 3.199797 |
| 4.27272 | 3.199595 |
| 4.30326 | 3.199394 |
| 4.33402 | 3.199192 |
| 4.36499 | 3.19899 |
| 4.39619 | 3.198788 |
| 4.42761 | 3.198586 |
| 4.45926 | 3.198384 |
| 4.49113 | 3.198181 |
| 4.52323 | 3.197979 |
| 4.55556 | 3.197775 |
| 4.58812 | 3.197572 |
| 4.62091 | 3.197368 |
| 4.65393 | 3.197164 |
| 4.6872 | 3.196959 |
| 4.7207 | 3.196753 |
| 4.75444 | 3.196547 |
| 4.78842 | 3.19634 |
| 4.82264 | 3.196133 |
| 4.85711 | 3.195924 |
| 4.89182 | 3.195715 |
| 4.92679 | 3.195505 |
| 4.962 | 3.195295 |
| 4.99746 | 3.195083 |
| 5.03318 | 3.19487 |
| 5.06915 | 3.194656 |
| 5.10538 | 3.194441 |
| 5.14187 | 3.194225 |
| 5.17862 | 3.194008 |
| 5.21564 | 3.193789 |
| 5.25291 | 3.19357 |
| 5.29046 | 3.193349 |
| 5.32827 | 3.193126 |
| 5.36635 | 3.192902 |
| 5.4047 | 3.192677 |
| 5.44333 | 3.192449 |
| 5.48224 | 3.192221 |
| 5.52142 | 3.19199 |
| 5.56088 | 3.191758 |
| 5.60063 | 3.191525 |
| 5.64066 | 3.191289 |
| 5.68097 | 3.191051 |
| 5.72157 | 3.190812 |
| 5.76247 | 3.19057 |
| 5.80365 | 3.190327 |
| 5.84513 | 3.190081 |
| 5.88691 | 3.189833 |
| 5.92898 | 3.189583 |
| 5.97136 | 3.189331 |
| 6.01404 | 3.189076 |
| 6.05702 | 3.188819 |
| 6.10031 | 3.188559 |
| 6.14391 | 3.188297 |
| 6.18782 | 3.188032 |
| 6.23205 | 3.187764 |
| 6.27659 | 3.187494 |
| 6.32145 | 3.187221 |
| 6.36663 | 3.186945 |
| 6.41213 | 3.186666 |
| 6.45796 | 3.186384 |
| 6.50412 | 3.186099 |
| 6.5506 | 3.18581 |
| 6.59742 | 3.185519 |
| 6.64457 | 3.185224 |
| 6.69206 | 3.184925 |
| 6.73989 | 3.184623 |
| 6.78807 | 3.184318 |
| 6.83658 | 3.184009 |
| 6.88544 | 3.183696 |
| 6.93465 | 3.183379 |
| 6.98422 | 3.183059 |
| 7.03414 | 3.182734 |
| 7.08441 | 3.182406 |
| 7.13504 | 3.182073 |
| 7.18604 | 3.181736 |
| 7.2374 | 3.181394 |
| 7.28913 | 3.181048 |
| 7.34122 | 3.180698 |
| 7.39369 | 3.180343 |
| 7.44654 | 3.179983 |
| 7.49976 | 3.179618 |
| 7.55336 | 3.179248 |
| 7.60734 | 3.178874 |
| 7.66172 | 3.178494 |
| 7.71647 | 3.178109 |
| 7.77163 | 3.177718 |
| 7.82717 | 3.177322 |
| 7.88311 | 3.17692 |
| 7.93946 | 3.176513 |
| 7.9962 | 3.176099 |
| 8.05335 | 3.17568 |
| 8.11091 | 3.175255 |
| 8.16888 | 3.174823 |
| 8.22726 | 3.174385 |
| 8.28607 | 3.17394 |
| 8.34529 | 3.173489 |
| 8.40493 | 3.173031 |
| 8.465 | 3.172566 |
| 8.5255 | 3.172094 |
| 8.58644 | 3.171615 |
| 8.64781 | 3.171128 |
| 8.70961 | 3.170634 |
| 8.77186 | 3.170132 |
| 8.83456 | 3.169622 |
| 8.8977 | 3.169104 |
| 8.96129 | 3.168578 |
| 9.02534 | 3.168044 |
| 9.08985 | 3.167501 |
| 9.15481 | 3.166949 |
| 9.22024 | 3.166388 |
| 9.28614 | 3.165818 |
| 9.35251 | 3.165239 |
| 9.41936 | 3.16465 |
| 9.48668 | 3.164052 |
| 9.55448 | 3.163443 |
| 9.62277 | 3.162825 |
| 9.69155 | 3.162196 |
| 9.76081 | 3.161556 |
| 9.83057 | 3.160905 |
| 9.90084 | 3.160244 |
| 9.9716 | 3.159571 |
| 10.0429 | 3.158886 |
| 10.1146 | 3.15819 |
| 10.1869 | 3.157481 |
| 10.2597 | 3.15676 |
| 10.3331 | 3.156026 |
| 10.4069 | 3.155279 |
| 10.4813 | 3.154519 |
| 10.5562 | 3.153746 |
| 10.6317 | 3.152958 |
| 10.7077 | 3.152157 |
| 10.7842 | 3.15134 |
| 10.8613 | 3.150509 |
| 10.9389 | 3.149663 |
| 11.0171 | 3.148801 |
| 11.0958 | 3.147923 |
| 11.1751 | 3.147028 |
| 11.255 | 3.146117 |
| 11.3354 | 3.145189 |
| 11.4164 | 3.144243 |
| 11.498 | 3.143279 |
| 11.5802 | 3.142297 |
| 11.663 | 3.141295 |
| 11.7463 | 3.140275 |
| 11.8303 | 3.139234 |
| 11.9148 | 3.138173 |
| 12 | 3.137091 |
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.