Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(o) 0.7–12 µm; 350 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 350 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
- 3.13922
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.85468
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.011901 µm⁻¹
- Group index ng
- 3.17373
- Group velocity dispersion
- 402.931 fs²/mm
- Dispersion parameter D
- -90.2475 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; 350 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-350K-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_560df9abd021/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-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_560df9abd021/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 | 3.64099213 |
| C2 | 5.14791199 |
| C3 | 0.13856847 |
| C4 | 2.16952994 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 350 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 | 3.437663 |
| 0.705003 | 3.431867 |
| 0.710042 | 3.426205 |
| 0.715117 | 3.420674 |
| 0.720228 | 3.41527 |
| 0.725375 | 3.40999 |
| 0.73056 | 3.404828 |
| 0.735781 | 3.399783 |
| 0.74104 | 3.39485 |
| 0.746336 | 3.390026 |
| 0.75167 | 3.385309 |
| 0.757043 | 3.380695 |
| 0.762453 | 3.37618 |
| 0.767903 | 3.371764 |
| 0.773391 | 3.367442 |
| 0.778919 | 3.363212 |
| 0.784486 | 3.359071 |
| 0.790093 | 3.355018 |
| 0.79574 | 3.35105 |
| 0.801427 | 3.347164 |
| 0.807155 | 3.343358 |
| 0.812924 | 3.339631 |
| 0.818734 | 3.33598 |
| 0.824585 | 3.332403 |
| 0.830479 | 3.328899 |
| 0.836414 | 3.325465 |
| 0.842392 | 3.3221 |
| 0.848413 | 3.318802 |
| 0.854477 | 3.315569 |
| 0.860584 | 3.3124 |
| 0.866735 | 3.309293 |
| 0.87293 | 3.306247 |
| 0.879169 | 3.30326 |
| 0.885452 | 3.30033 |
| 0.891781 | 3.297457 |
| 0.898154 | 3.294639 |
| 0.904574 | 3.291875 |
| 0.911039 | 3.289164 |
| 0.91755 | 3.286503 |
| 0.924108 | 3.283893 |
| 0.930713 | 3.281331 |
| 0.937365 | 3.278818 |
| 0.944064 | 3.276351 |
| 0.950812 | 3.273929 |
| 0.957607 | 3.271553 |
| 0.964451 | 3.26922 |
| 0.971345 | 3.266929 |
| 0.978287 | 3.26468 |
| 0.985279 | 3.262473 |
| 0.992321 | 3.260305 |
| 0.999413 | 3.258176 |
| 1.00656 | 3.256085 |
| 1.01375 | 3.254031 |
| 1.021 | 3.252015 |
| 1.02829 | 3.250033 |
| 1.03564 | 3.248087 |
| 1.04304 | 3.246176 |
| 1.0505 | 3.244298 |
| 1.05801 | 3.242452 |
| 1.06557 | 3.240639 |
| 1.07318 | 3.238858 |
| 1.08085 | 3.237107 |
| 1.08858 | 3.235387 |
| 1.09636 | 3.233696 |
| 1.1042 | 3.232034 |
| 1.11209 | 3.230401 |
| 1.12004 | 3.228795 |
| 1.12804 | 3.227217 |
| 1.1361 | 3.225665 |
| 1.14422 | 3.22414 |
| 1.1524 | 3.222641 |
| 1.16064 | 3.221166 |
| 1.16893 | 3.219717 |
| 1.17729 | 3.218292 |
| 1.1857 | 3.21689 |
| 1.19418 | 3.215512 |
| 1.20271 | 3.214156 |
| 1.21131 | 3.212823 |
| 1.21997 | 3.211512 |
| 1.22868 | 3.210222 |
| 1.23747 | 3.208954 |
| 1.24631 | 3.207706 |
| 1.25522 | 3.206479 |
| 1.26419 | 3.205271 |
| 1.27322 | 3.204084 |
| 1.28232 | 3.202915 |
| 1.29149 | 3.201765 |
| 1.30072 | 3.200634 |
| 1.31002 | 3.199521 |
| 1.31938 | 3.198426 |
| 1.32881 | 3.197348 |
| 1.33831 | 3.196287 |
| 1.34787 | 3.195243 |
| 1.35751 | 3.194216 |
| 1.36721 | 3.193205 |
| 1.37698 | 3.19221 |
| 1.38682 | 3.191231 |
| 1.39673 | 3.190267 |
| 1.40672 | 3.189318 |
| 1.41677 | 3.188384 |
| 1.4269 | 3.187464 |
| 1.43709 | 3.186559 |
| 1.44736 | 3.185668 |
| 1.45771 | 3.18479 |
| 1.46813 | 3.183927 |
| 1.47862 | 3.183076 |
| 1.48919 | 3.182239 |
| 1.49983 | 3.181414 |
| 1.51055 | 3.180602 |
| 1.52135 | 3.179802 |
| 1.53222 | 3.179015 |
| 1.54317 | 3.178239 |
| 1.5542 | 3.177475 |
| 1.56531 | 3.176723 |
| 1.5765 | 3.175982 |
| 1.58776 | 3.175252 |
| 1.59911 | 3.174533 |
| 1.61054 | 3.173825 |
| 1.62205 | 3.173128 |
| 1.63365 | 3.17244 |
| 1.64532 | 3.171763 |
| 1.65708 | 3.171096 |
| 1.66892 | 3.170439 |
| 1.68085 | 3.169792 |
| 1.69287 | 3.169154 |
| 1.70497 | 3.168525 |
| 1.71715 | 3.167906 |
| 1.72942 | 3.167295 |
| 1.74178 | 3.166694 |
| 1.75423 | 3.166101 |
| 1.76677 | 3.165517 |
| 1.7794 | 3.164941 |
| 1.79212 | 3.164373 |
| 1.80492 | 3.163814 |
| 1.81782 | 3.163262 |
| 1.83082 | 3.162718 |
| 1.8439 | 3.162182 |
| 1.85708 | 3.161654 |
| 1.87035 | 3.161133 |
| 1.88372 | 3.16062 |
| 1.89719 | 3.160113 |
| 1.91074 | 3.159614 |
| 1.9244 | 3.159122 |
| 1.93816 | 3.158636 |
| 1.95201 | 3.158157 |
| 1.96596 | 3.157685 |
| 1.98001 | 3.157219 |
| 1.99416 | 3.15676 |
| 2.00841 | 3.156307 |
| 2.02277 | 3.15586 |
| 2.03723 | 3.155419 |
| 2.05179 | 3.154984 |
| 2.06645 | 3.154554 |
| 2.08122 | 3.154131 |
| 2.09609 | 3.153713 |
| 2.11108 | 3.153301 |
| 2.12616 | 3.152894 |
| 2.14136 | 3.152492 |
| 2.15666 | 3.152096 |
| 2.17208 | 3.151705 |
| 2.1876 | 3.151319 |
| 2.20324 | 3.150938 |
| 2.21899 | 3.150561 |
| 2.23484 | 3.15019 |
| 2.25082 | 3.149823 |
| 2.2669 | 3.149461 |
| 2.28311 | 3.149103 |
| 2.29942 | 3.14875 |
| 2.31586 | 3.148401 |
| 2.33241 | 3.148057 |
| 2.34908 | 3.147717 |
| 2.36587 | 3.147381 |
| 2.38278 | 3.147048 |
| 2.39981 | 3.14672 |
| 2.41696 | 3.146396 |
| 2.43424 | 3.146076 |
| 2.45163 | 3.145759 |
| 2.46916 | 3.145446 |
| 2.4868 | 3.145137 |
| 2.50458 | 3.144831 |
| 2.52248 | 3.144529 |
| 2.54051 | 3.14423 |
| 2.55866 | 3.143934 |
| 2.57695 | 3.143642 |
| 2.59537 | 3.143353 |
| 2.61392 | 3.143067 |
| 2.6326 | 3.142784 |
| 2.65142 | 3.142505 |
| 2.67037 | 3.142228 |
| 2.68945 | 3.141954 |
| 2.70867 | 3.141683 |
| 2.72803 | 3.141414 |
| 2.74753 | 3.141149 |
| 2.76717 | 3.140886 |
| 2.78695 | 3.140625 |
| 2.80686 | 3.140368 |
| 2.82693 | 3.140112 |
| 2.84713 | 3.139859 |
| 2.86748 | 3.139609 |
| 2.88797 | 3.13936 |
| 2.90861 | 3.139114 |
| 2.9294 | 3.138871 |
| 2.95034 | 3.138629 |
| 2.97143 | 3.13839 |
| 2.99266 | 3.138152 |
| 3.01405 | 3.137917 |
| 3.03559 | 3.137683 |
| 3.05729 | 3.137451 |
| 3.07914 | 3.137222 |
| 3.10115 | 3.136994 |
| 3.12331 | 3.136767 |
| 3.14564 | 3.136543 |
| 3.16812 | 3.13632 |
| 3.19076 | 3.136099 |
| 3.21357 | 3.135879 |
| 3.23653 | 3.13566 |
| 3.25967 | 3.135444 |
| 3.28296 | 3.135228 |
| 3.30643 | 3.135014 |
| 3.33006 | 3.134801 |
| 3.35386 | 3.13459 |
| 3.37783 | 3.13438 |
| 3.40197 | 3.134171 |
| 3.42629 | 3.133963 |
| 3.45078 | 3.133756 |
| 3.47544 | 3.13355 |
| 3.50028 | 3.133345 |
| 3.5253 | 3.133141 |
| 3.55049 | 3.132938 |
| 3.57587 | 3.132736 |
| 3.60142 | 3.132535 |
| 3.62716 | 3.132334 |
| 3.65309 | 3.132134 |
| 3.6792 | 3.131935 |
| 3.70549 | 3.131737 |
| 3.73198 | 3.131539 |
| 3.75865 | 3.131341 |
| 3.78551 | 3.131145 |
| 3.81257 | 3.130948 |
| 3.83982 | 3.130752 |
| 3.86726 | 3.130557 |
| 3.8949 | 3.130362 |
| 3.92274 | 3.130167 |
| 3.95078 | 3.129972 |
| 3.97901 | 3.129778 |
| 4.00745 | 3.129583 |
| 4.03609 | 3.129389 |
| 4.06494 | 3.129195 |
| 4.09399 | 3.129001 |
| 4.12325 | 3.128807 |
| 4.15272 | 3.128613 |
| 4.1824 | 3.128419 |
| 4.2123 | 3.128225 |
| 4.2424 | 3.128031 |
| 4.27272 | 3.127836 |
| 4.30326 | 3.127641 |
| 4.33402 | 3.127446 |
| 4.36499 | 3.12725 |
| 4.39619 | 3.127055 |
| 4.42761 | 3.126858 |
| 4.45926 | 3.126661 |
| 4.49113 | 3.126464 |
| 4.52323 | 3.126266 |
| 4.55556 | 3.126068 |
| 4.58812 | 3.125869 |
| 4.62091 | 3.125669 |
| 4.65393 | 3.125468 |
| 4.6872 | 3.125267 |
| 4.7207 | 3.125065 |
| 4.75444 | 3.124862 |
| 4.78842 | 3.124658 |
| 4.82264 | 3.124453 |
| 4.85711 | 3.124247 |
| 4.89182 | 3.12404 |
| 4.92679 | 3.123832 |
| 4.962 | 3.123623 |
| 4.99746 | 3.123412 |
| 5.03318 | 3.123201 |
| 5.06915 | 3.122988 |
| 5.10538 | 3.122773 |
| 5.14187 | 3.122557 |
| 5.17862 | 3.12234 |
| 5.21564 | 3.122121 |
| 5.25291 | 3.121901 |
| 5.29046 | 3.121679 |
| 5.32827 | 3.121456 |
| 5.36635 | 3.121231 |
| 5.4047 | 3.121004 |
| 5.44333 | 3.120775 |
| 5.48224 | 3.120544 |
| 5.52142 | 3.120311 |
| 5.56088 | 3.120077 |
| 5.60063 | 3.11984 |
| 5.64066 | 3.119602 |
| 5.68097 | 3.119361 |
| 5.72157 | 3.119118 |
| 5.76247 | 3.118872 |
| 5.80365 | 3.118625 |
| 5.84513 | 3.118374 |
| 5.88691 | 3.118122 |
| 5.92898 | 3.117867 |
| 5.97136 | 3.117609 |
| 6.01404 | 3.117349 |
| 6.05702 | 3.117086 |
| 6.10031 | 3.11682 |
| 6.14391 | 3.116552 |
| 6.18782 | 3.11628 |
| 6.23205 | 3.116006 |
| 6.27659 | 3.115728 |
| 6.32145 | 3.115447 |
| 6.36663 | 3.115164 |
| 6.41213 | 3.114876 |
| 6.45796 | 3.114586 |
| 6.50412 | 3.114292 |
| 6.5506 | 3.113995 |
| 6.59742 | 3.113694 |
| 6.64457 | 3.113389 |
| 6.69206 | 3.113081 |
| 6.73989 | 3.112769 |
| 6.78807 | 3.112453 |
| 6.83658 | 3.112133 |
| 6.88544 | 3.111809 |
| 6.93465 | 3.111481 |
| 6.98422 | 3.111148 |
| 7.03414 | 3.110812 |
| 7.08441 | 3.11047 |
| 7.13504 | 3.110125 |
| 7.18604 | 3.109774 |
| 7.2374 | 3.109419 |
| 7.28913 | 3.10906 |
| 7.34122 | 3.108695 |
| 7.39369 | 3.108325 |
| 7.44654 | 3.10795 |
| 7.49976 | 3.10757 |
| 7.55336 | 3.107185 |
| 7.60734 | 3.106794 |
| 7.66172 | 3.106397 |
| 7.71647 | 3.105995 |
| 7.77163 | 3.105587 |
| 7.82717 | 3.105174 |
| 7.88311 | 3.104754 |
| 7.93946 | 3.104328 |
| 7.9962 | 3.103895 |
| 8.05335 | 3.103457 |
| 8.11091 | 3.103011 |
| 8.16888 | 3.102559 |
| 8.22726 | 3.1021 |
| 8.28607 | 3.101635 |
| 8.34529 | 3.101162 |
| 8.40493 | 3.100682 |
| 8.465 | 3.100194 |
| 8.5255 | 3.099699 |
| 8.58644 | 3.099196 |
| 8.64781 | 3.098685 |
| 8.70961 | 3.098166 |
| 8.77186 | 3.097639 |
| 8.83456 | 3.097103 |
| 8.8977 | 3.096559 |
| 8.96129 | 3.096006 |
| 9.02534 | 3.095445 |
| 9.08985 | 3.094874 |
| 9.15481 | 3.094293 |
| 9.22024 | 3.093703 |
| 9.28614 | 3.093104 |
| 9.35251 | 3.092494 |
| 9.41936 | 3.091875 |
| 9.48668 | 3.091244 |
| 9.55448 | 3.090604 |
| 9.62277 | 3.089952 |
| 9.69155 | 3.08929 |
| 9.76081 | 3.088616 |
| 9.83057 | 3.08793 |
| 9.90084 | 3.087233 |
| 9.9716 | 3.086523 |
| 10.0429 | 3.085802 |
| 10.1146 | 3.085067 |
| 10.1869 | 3.08432 |
| 10.2597 | 3.083559 |
| 10.3331 | 3.082785 |
| 10.4069 | 3.081997 |
| 10.4813 | 3.081195 |
| 10.5562 | 3.080379 |
| 10.6317 | 3.079548 |
| 10.7077 | 3.078701 |
| 10.7842 | 3.077839 |
| 10.8613 | 3.076962 |
| 10.9389 | 3.076068 |
| 11.0171 | 3.075157 |
| 11.0958 | 3.07423 |
| 11.1751 | 3.073285 |
| 11.255 | 3.072322 |
| 11.3354 | 3.071341 |
| 11.4164 | 3.070341 |
| 11.498 | 3.069322 |
| 11.5802 | 3.068284 |
| 11.663 | 3.067225 |
| 11.7463 | 3.066146 |
| 11.8303 | 3.065046 |
| 11.9148 | 3.063924 |
| 12 | 3.06278 |
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.