Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(o) 0.7–12 µm; 400 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 400 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
- 3.1481
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.91054
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0121044 µm⁻¹
- Group index ng
- 3.1832
- Group velocity dispersion
- 412.723 fs²/mm
- Dispersion parameter D
- -92.4406 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; 400 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-400K-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_d211a19fc9e9/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-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_d211a19fc9e9/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 | 3.66484235 |
| C2 | 5.1778262 |
| C3 | 0.1410793 |
| C4 | 2.16968693 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 400 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 | 3.454713 |
| 0.705003 | 3.448721 |
| 0.710042 | 3.442871 |
| 0.715117 | 3.437157 |
| 0.720228 | 3.431576 |
| 0.725375 | 3.426123 |
| 0.73056 | 3.420794 |
| 0.735781 | 3.415586 |
| 0.74104 | 3.410495 |
| 0.746336 | 3.405519 |
| 0.75167 | 3.400652 |
| 0.757043 | 3.395893 |
| 0.762453 | 3.391238 |
| 0.767903 | 3.386684 |
| 0.773391 | 3.382228 |
| 0.778919 | 3.377869 |
| 0.784486 | 3.373602 |
| 0.790093 | 3.369426 |
| 0.79574 | 3.365337 |
| 0.801427 | 3.361335 |
| 0.807155 | 3.357416 |
| 0.812924 | 3.353578 |
| 0.818734 | 3.349819 |
| 0.824585 | 3.346137 |
| 0.830479 | 3.34253 |
| 0.836414 | 3.338996 |
| 0.842392 | 3.335534 |
| 0.848413 | 3.332141 |
| 0.854477 | 3.328815 |
| 0.860584 | 3.325555 |
| 0.866735 | 3.32236 |
| 0.87293 | 3.319228 |
| 0.879169 | 3.316156 |
| 0.885452 | 3.313145 |
| 0.891781 | 3.310191 |
| 0.898154 | 3.307295 |
| 0.904574 | 3.304454 |
| 0.911039 | 3.301668 |
| 0.91755 | 3.298934 |
| 0.924108 | 3.296252 |
| 0.930713 | 3.293621 |
| 0.937365 | 3.291039 |
| 0.944064 | 3.288505 |
| 0.950812 | 3.286018 |
| 0.957607 | 3.283578 |
| 0.964451 | 3.281182 |
| 0.971345 | 3.278831 |
| 0.978287 | 3.276522 |
| 0.985279 | 3.274256 |
| 0.992321 | 3.27203 |
| 0.999413 | 3.269845 |
| 1.00656 | 3.2677 |
| 1.01375 | 3.265593 |
| 1.021 | 3.263523 |
| 1.02829 | 3.261491 |
| 1.03564 | 3.259494 |
| 1.04304 | 3.257533 |
| 1.0505 | 3.255607 |
| 1.05801 | 3.253714 |
| 1.06557 | 3.251854 |
| 1.07318 | 3.250027 |
| 1.08085 | 3.248232 |
| 1.08858 | 3.246468 |
| 1.09636 | 3.244734 |
| 1.1042 | 3.243031 |
| 1.11209 | 3.241356 |
| 1.12004 | 3.23971 |
| 1.12804 | 3.238093 |
| 1.1361 | 3.236502 |
| 1.14422 | 3.234939 |
| 1.1524 | 3.233402 |
| 1.16064 | 3.231892 |
| 1.16893 | 3.230406 |
| 1.17729 | 3.228946 |
| 1.1857 | 3.22751 |
| 1.19418 | 3.226097 |
| 1.20271 | 3.224709 |
| 1.21131 | 3.223343 |
| 1.21997 | 3.222 |
| 1.22868 | 3.220679 |
| 1.23747 | 3.21938 |
| 1.24631 | 3.218102 |
| 1.25522 | 3.216845 |
| 1.26419 | 3.215608 |
| 1.27322 | 3.214392 |
| 1.28232 | 3.213195 |
| 1.29149 | 3.212018 |
| 1.30072 | 3.21086 |
| 1.31002 | 3.20972 |
| 1.31938 | 3.208599 |
| 1.32881 | 3.207496 |
| 1.33831 | 3.20641 |
| 1.34787 | 3.205341 |
| 1.35751 | 3.20429 |
| 1.36721 | 3.203255 |
| 1.37698 | 3.202237 |
| 1.38682 | 3.201234 |
| 1.39673 | 3.200248 |
| 1.40672 | 3.199277 |
| 1.41677 | 3.198321 |
| 1.4269 | 3.19738 |
| 1.43709 | 3.196454 |
| 1.44736 | 3.195542 |
| 1.45771 | 3.194644 |
| 1.46813 | 3.19376 |
| 1.47862 | 3.19289 |
| 1.48919 | 3.192033 |
| 1.49983 | 3.19119 |
| 1.51055 | 3.190359 |
| 1.52135 | 3.189541 |
| 1.53222 | 3.188736 |
| 1.54317 | 3.187943 |
| 1.5542 | 3.187161 |
| 1.56531 | 3.186392 |
| 1.5765 | 3.185634 |
| 1.58776 | 3.184888 |
| 1.59911 | 3.184153 |
| 1.61054 | 3.183429 |
| 1.62205 | 3.182715 |
| 1.63365 | 3.182013 |
| 1.64532 | 3.181321 |
| 1.65708 | 3.180639 |
| 1.66892 | 3.179967 |
| 1.68085 | 3.179305 |
| 1.69287 | 3.178653 |
| 1.70497 | 3.17801 |
| 1.71715 | 3.177377 |
| 1.72942 | 3.176753 |
| 1.74178 | 3.176138 |
| 1.75423 | 3.175532 |
| 1.76677 | 3.174935 |
| 1.7794 | 3.174347 |
| 1.79212 | 3.173767 |
| 1.80492 | 3.173195 |
| 1.81782 | 3.172631 |
| 1.83082 | 3.172076 |
| 1.8439 | 3.171528 |
| 1.85708 | 3.170988 |
| 1.87035 | 3.170456 |
| 1.88372 | 3.169932 |
| 1.89719 | 3.169414 |
| 1.91074 | 3.168904 |
| 1.9244 | 3.168401 |
| 1.93816 | 3.167905 |
| 1.95201 | 3.167416 |
| 1.96596 | 3.166934 |
| 1.98001 | 3.166458 |
| 1.99416 | 3.165989 |
| 2.00841 | 3.165526 |
| 2.02277 | 3.16507 |
| 2.03723 | 3.16462 |
| 2.05179 | 3.164176 |
| 2.06645 | 3.163737 |
| 2.08122 | 3.163305 |
| 2.09609 | 3.162879 |
| 2.11108 | 3.162458 |
| 2.12616 | 3.162042 |
| 2.14136 | 3.161633 |
| 2.15666 | 3.161228 |
| 2.17208 | 3.160829 |
| 2.1876 | 3.160435 |
| 2.20324 | 3.160046 |
| 2.21899 | 3.159662 |
| 2.23484 | 3.159283 |
| 2.25082 | 3.158909 |
| 2.2669 | 3.158539 |
| 2.28311 | 3.158175 |
| 2.29942 | 3.157814 |
| 2.31586 | 3.157459 |
| 2.33241 | 3.157107 |
| 2.34908 | 3.15676 |
| 2.36587 | 3.156417 |
| 2.38278 | 3.156079 |
| 2.39981 | 3.155744 |
| 2.41696 | 3.155414 |
| 2.43424 | 3.155087 |
| 2.45163 | 3.154764 |
| 2.46916 | 3.154445 |
| 2.4868 | 3.15413 |
| 2.50458 | 3.153818 |
| 2.52248 | 3.15351 |
| 2.54051 | 3.153206 |
| 2.55866 | 3.152905 |
| 2.57695 | 3.152607 |
| 2.59537 | 3.152312 |
| 2.61392 | 3.152021 |
| 2.6326 | 3.151733 |
| 2.65142 | 3.151448 |
| 2.67037 | 3.151166 |
| 2.68945 | 3.150887 |
| 2.70867 | 3.150611 |
| 2.72803 | 3.150338 |
| 2.74753 | 3.150068 |
| 2.76717 | 3.1498 |
| 2.78695 | 3.149535 |
| 2.80686 | 3.149272 |
| 2.82693 | 3.149013 |
| 2.84713 | 3.148755 |
| 2.86748 | 3.1485 |
| 2.88797 | 3.148248 |
| 2.90861 | 3.147998 |
| 2.9294 | 3.14775 |
| 2.95034 | 3.147504 |
| 2.97143 | 3.147261 |
| 2.99266 | 3.147019 |
| 3.01405 | 3.14678 |
| 3.03559 | 3.146542 |
| 3.05729 | 3.146307 |
| 3.07914 | 3.146074 |
| 3.10115 | 3.145842 |
| 3.12331 | 3.145612 |
| 3.14564 | 3.145384 |
| 3.16812 | 3.145158 |
| 3.19076 | 3.144933 |
| 3.21357 | 3.14471 |
| 3.23653 | 3.144488 |
| 3.25967 | 3.144268 |
| 3.28296 | 3.144049 |
| 3.30643 | 3.143832 |
| 3.33006 | 3.143616 |
| 3.35386 | 3.143402 |
| 3.37783 | 3.143188 |
| 3.40197 | 3.142976 |
| 3.42629 | 3.142766 |
| 3.45078 | 3.142556 |
| 3.47544 | 3.142347 |
| 3.50028 | 3.14214 |
| 3.5253 | 3.141933 |
| 3.55049 | 3.141727 |
| 3.57587 | 3.141522 |
| 3.60142 | 3.141319 |
| 3.62716 | 3.141115 |
| 3.65309 | 3.140913 |
| 3.6792 | 3.140712 |
| 3.70549 | 3.140511 |
| 3.73198 | 3.14031 |
| 3.75865 | 3.140111 |
| 3.78551 | 3.139912 |
| 3.81257 | 3.139713 |
| 3.83982 | 3.139515 |
| 3.86726 | 3.139317 |
| 3.8949 | 3.13912 |
| 3.92274 | 3.138923 |
| 3.95078 | 3.138726 |
| 3.97901 | 3.13853 |
| 4.00745 | 3.138334 |
| 4.03609 | 3.138138 |
| 4.06494 | 3.137942 |
| 4.09399 | 3.137746 |
| 4.12325 | 3.13755 |
| 4.15272 | 3.137354 |
| 4.1824 | 3.137158 |
| 4.2123 | 3.136962 |
| 4.2424 | 3.136766 |
| 4.27272 | 3.13657 |
| 4.30326 | 3.136373 |
| 4.33402 | 3.136177 |
| 4.36499 | 3.13598 |
| 4.39619 | 3.135782 |
| 4.42761 | 3.135584 |
| 4.45926 | 3.135386 |
| 4.49113 | 3.135187 |
| 4.52323 | 3.134988 |
| 4.55556 | 3.134788 |
| 4.58812 | 3.134588 |
| 4.62091 | 3.134387 |
| 4.65393 | 3.134185 |
| 4.6872 | 3.133982 |
| 4.7207 | 3.133779 |
| 4.75444 | 3.133574 |
| 4.78842 | 3.133369 |
| 4.82264 | 3.133163 |
| 4.85711 | 3.132956 |
| 4.89182 | 3.132748 |
| 4.92679 | 3.132539 |
| 4.962 | 3.132329 |
| 4.99746 | 3.132117 |
| 5.03318 | 3.131904 |
| 5.06915 | 3.13169 |
| 5.10538 | 3.131475 |
| 5.14187 | 3.131258 |
| 5.17862 | 3.13104 |
| 5.21564 | 3.130821 |
| 5.25291 | 3.1306 |
| 5.29046 | 3.130377 |
| 5.32827 | 3.130153 |
| 5.36635 | 3.129927 |
| 5.4047 | 3.129699 |
| 5.44333 | 3.129469 |
| 5.48224 | 3.129238 |
| 5.52142 | 3.129005 |
| 5.56088 | 3.128769 |
| 5.60063 | 3.128532 |
| 5.64066 | 3.128293 |
| 5.68097 | 3.128051 |
| 5.72157 | 3.127808 |
| 5.76247 | 3.127562 |
| 5.80365 | 3.127314 |
| 5.84513 | 3.127063 |
| 5.88691 | 3.12681 |
| 5.92898 | 3.126554 |
| 5.97136 | 3.126296 |
| 6.01404 | 3.126036 |
| 6.05702 | 3.125772 |
| 6.10031 | 3.125506 |
| 6.14391 | 3.125237 |
| 6.18782 | 3.124966 |
| 6.23205 | 3.124691 |
| 6.27659 | 3.124413 |
| 6.32145 | 3.124132 |
| 6.36663 | 3.123848 |
| 6.41213 | 3.123561 |
| 6.45796 | 3.12327 |
| 6.50412 | 3.122976 |
| 6.5506 | 3.122679 |
| 6.59742 | 3.122378 |
| 6.64457 | 3.122073 |
| 6.69206 | 3.121765 |
| 6.73989 | 3.121453 |
| 6.78807 | 3.121137 |
| 6.83658 | 3.120817 |
| 6.88544 | 3.120493 |
| 6.93465 | 3.120165 |
| 6.98422 | 3.119832 |
| 7.03414 | 3.119496 |
| 7.08441 | 3.119155 |
| 7.13504 | 3.118809 |
| 7.18604 | 3.118459 |
| 7.2374 | 3.118104 |
| 7.28913 | 3.117744 |
| 7.34122 | 3.11738 |
| 7.39369 | 3.117011 |
| 7.44654 | 3.116636 |
| 7.49976 | 3.116256 |
| 7.55336 | 3.115871 |
| 7.60734 | 3.115481 |
| 7.66172 | 3.115085 |
| 7.71647 | 3.114683 |
| 7.77163 | 3.114275 |
| 7.82717 | 3.113862 |
| 7.88311 | 3.113443 |
| 7.93946 | 3.113017 |
| 7.9962 | 3.112585 |
| 8.05335 | 3.112147 |
| 8.11091 | 3.111703 |
| 8.16888 | 3.111251 |
| 8.22726 | 3.110793 |
| 8.28607 | 3.110328 |
| 8.34529 | 3.109856 |
| 8.40493 | 3.109376 |
| 8.465 | 3.108889 |
| 8.5255 | 3.108395 |
| 8.58644 | 3.107893 |
| 8.64781 | 3.107383 |
| 8.70961 | 3.106865 |
| 8.77186 | 3.106339 |
| 8.83456 | 3.105804 |
| 8.8977 | 3.105261 |
| 8.96129 | 3.104709 |
| 9.02534 | 3.104148 |
| 9.08985 | 3.103578 |
| 9.15481 | 3.102999 |
| 9.22024 | 3.102411 |
| 9.28614 | 3.101812 |
| 9.35251 | 3.101204 |
| 9.41936 | 3.100585 |
| 9.48668 | 3.099957 |
| 9.55448 | 3.099317 |
| 9.62277 | 3.098667 |
| 9.69155 | 3.098006 |
| 9.76081 | 3.097333 |
| 9.83057 | 3.096649 |
| 9.90084 | 3.095953 |
| 9.9716 | 3.095245 |
| 10.0429 | 3.094525 |
| 10.1146 | 3.093792 |
| 10.1869 | 3.093047 |
| 10.2597 | 3.092288 |
| 10.3331 | 3.091516 |
| 10.4069 | 3.090729 |
| 10.4813 | 3.089929 |
| 10.5562 | 3.089115 |
| 10.6317 | 3.088285 |
| 10.7077 | 3.087441 |
| 10.7842 | 3.086581 |
| 10.8613 | 3.085706 |
| 10.9389 | 3.084814 |
| 11.0171 | 3.083905 |
| 11.0958 | 3.08298 |
| 11.1751 | 3.082037 |
| 11.255 | 3.081077 |
| 11.3354 | 3.080098 |
| 11.4164 | 3.079101 |
| 11.498 | 3.078085 |
| 11.5802 | 3.077049 |
| 11.663 | 3.075993 |
| 11.7463 | 3.074917 |
| 11.8303 | 3.073819 |
| 11.9148 | 3.0727 |
| 12 | 3.071559 |
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.