Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(o) 0.7–12 µm; 450 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 450 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
- 3.15836
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.97521
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.012337 µm⁻¹
- Group index ng
- 3.19413
- Group velocity dispersion
- 423.918 fs²/mm
- Dispersion parameter D
- -94.9481 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; 450 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-450K-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_937d58830c83/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-1998-450k-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_937d58830c83/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 | 3.68535622 |
| C2 | 5.21956368 |
| C3 | 0.14373622 |
| C4 | 2.16981674 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 450 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 | 3.47425 |
| 0.705003 | 3.468038 |
| 0.710042 | 3.461973 |
| 0.715117 | 3.456052 |
| 0.720228 | 3.450269 |
| 0.725375 | 3.44462 |
| 0.73056 | 3.439101 |
| 0.735781 | 3.433709 |
| 0.74104 | 3.428439 |
| 0.746336 | 3.423288 |
| 0.75167 | 3.418252 |
| 0.757043 | 3.413329 |
| 0.762453 | 3.408514 |
| 0.767903 | 3.403804 |
| 0.773391 | 3.399197 |
| 0.778919 | 3.39469 |
| 0.784486 | 3.39028 |
| 0.790093 | 3.385964 |
| 0.79574 | 3.38174 |
| 0.801427 | 3.377605 |
| 0.807155 | 3.373557 |
| 0.812924 | 3.369594 |
| 0.818734 | 3.365712 |
| 0.824585 | 3.361911 |
| 0.830479 | 3.358188 |
| 0.836414 | 3.354541 |
| 0.842392 | 3.350967 |
| 0.848413 | 3.347466 |
| 0.854477 | 3.344035 |
| 0.860584 | 3.340673 |
| 0.866735 | 3.337377 |
| 0.87293 | 3.334146 |
| 0.879169 | 3.33098 |
| 0.885452 | 3.327875 |
| 0.891781 | 3.32483 |
| 0.898154 | 3.321845 |
| 0.904574 | 3.318917 |
| 0.911039 | 3.316045 |
| 0.91755 | 3.313228 |
| 0.924108 | 3.310465 |
| 0.930713 | 3.307754 |
| 0.937365 | 3.305095 |
| 0.944064 | 3.302485 |
| 0.950812 | 3.299924 |
| 0.957607 | 3.297411 |
| 0.964451 | 3.294944 |
| 0.971345 | 3.292523 |
| 0.978287 | 3.290147 |
| 0.985279 | 3.287814 |
| 0.992321 | 3.285523 |
| 0.999413 | 3.283274 |
| 1.00656 | 3.281066 |
| 1.01375 | 3.278898 |
| 1.021 | 3.276769 |
| 1.02829 | 3.274678 |
| 1.03564 | 3.272624 |
| 1.04304 | 3.270607 |
| 1.0505 | 3.268625 |
| 1.05801 | 3.266678 |
| 1.06557 | 3.264766 |
| 1.07318 | 3.262887 |
| 1.08085 | 3.261041 |
| 1.08858 | 3.259228 |
| 1.09636 | 3.257445 |
| 1.1042 | 3.255694 |
| 1.11209 | 3.253972 |
| 1.12004 | 3.252281 |
| 1.12804 | 3.250618 |
| 1.1361 | 3.248984 |
| 1.14422 | 3.247377 |
| 1.1524 | 3.245798 |
| 1.16064 | 3.244246 |
| 1.16893 | 3.242719 |
| 1.17729 | 3.241219 |
| 1.1857 | 3.239744 |
| 1.19418 | 3.238293 |
| 1.20271 | 3.236866 |
| 1.21131 | 3.235464 |
| 1.21997 | 3.234084 |
| 1.22868 | 3.232727 |
| 1.23747 | 3.231393 |
| 1.24631 | 3.230081 |
| 1.25522 | 3.22879 |
| 1.26419 | 3.22752 |
| 1.27322 | 3.226272 |
| 1.28232 | 3.225043 |
| 1.29149 | 3.223834 |
| 1.30072 | 3.222645 |
| 1.31002 | 3.221475 |
| 1.31938 | 3.220324 |
| 1.32881 | 3.219192 |
| 1.33831 | 3.218077 |
| 1.34787 | 3.216981 |
| 1.35751 | 3.215902 |
| 1.36721 | 3.21484 |
| 1.37698 | 3.213795 |
| 1.38682 | 3.212766 |
| 1.39673 | 3.211754 |
| 1.40672 | 3.210758 |
| 1.41677 | 3.209777 |
| 1.4269 | 3.208812 |
| 1.43709 | 3.207861 |
| 1.44736 | 3.206926 |
| 1.45771 | 3.206005 |
| 1.46813 | 3.205098 |
| 1.47862 | 3.204206 |
| 1.48919 | 3.203327 |
| 1.49983 | 3.202462 |
| 1.51055 | 3.20161 |
| 1.52135 | 3.200771 |
| 1.53222 | 3.199945 |
| 1.54317 | 3.199132 |
| 1.5542 | 3.198331 |
| 1.56531 | 3.197542 |
| 1.5765 | 3.196765 |
| 1.58776 | 3.196 |
| 1.59911 | 3.195246 |
| 1.61054 | 3.194504 |
| 1.62205 | 3.193773 |
| 1.63365 | 3.193052 |
| 1.64532 | 3.192343 |
| 1.65708 | 3.191644 |
| 1.66892 | 3.190955 |
| 1.68085 | 3.190277 |
| 1.69287 | 3.189609 |
| 1.70497 | 3.18895 |
| 1.71715 | 3.188301 |
| 1.72942 | 3.187662 |
| 1.74178 | 3.187032 |
| 1.75423 | 3.186411 |
| 1.76677 | 3.185799 |
| 1.7794 | 3.185196 |
| 1.79212 | 3.184602 |
| 1.80492 | 3.184016 |
| 1.81782 | 3.183439 |
| 1.83082 | 3.18287 |
| 1.8439 | 3.182309 |
| 1.85708 | 3.181756 |
| 1.87035 | 3.181211 |
| 1.88372 | 3.180674 |
| 1.89719 | 3.180144 |
| 1.91074 | 3.179622 |
| 1.9244 | 3.179107 |
| 1.93816 | 3.178599 |
| 1.95201 | 3.178098 |
| 1.96596 | 3.177605 |
| 1.98001 | 3.177118 |
| 1.99416 | 3.176637 |
| 2.00841 | 3.176164 |
| 2.02277 | 3.175696 |
| 2.03723 | 3.175236 |
| 2.05179 | 3.174781 |
| 2.06645 | 3.174333 |
| 2.08122 | 3.17389 |
| 2.09609 | 3.173454 |
| 2.11108 | 3.173023 |
| 2.12616 | 3.172598 |
| 2.14136 | 3.172179 |
| 2.15666 | 3.171765 |
| 2.17208 | 3.171356 |
| 2.1876 | 3.170953 |
| 2.20324 | 3.170556 |
| 2.21899 | 3.170163 |
| 2.23484 | 3.169775 |
| 2.25082 | 3.169393 |
| 2.2669 | 3.169015 |
| 2.28311 | 3.168642 |
| 2.29942 | 3.168273 |
| 2.31586 | 3.16791 |
| 2.33241 | 3.16755 |
| 2.34908 | 3.167196 |
| 2.36587 | 3.166845 |
| 2.38278 | 3.166499 |
| 2.39981 | 3.166157 |
| 2.41696 | 3.165819 |
| 2.43424 | 3.165486 |
| 2.45163 | 3.165156 |
| 2.46916 | 3.16483 |
| 2.4868 | 3.164508 |
| 2.50458 | 3.16419 |
| 2.52248 | 3.163875 |
| 2.54051 | 3.163564 |
| 2.55866 | 3.163256 |
| 2.57695 | 3.162952 |
| 2.59537 | 3.162652 |
| 2.61392 | 3.162354 |
| 2.6326 | 3.16206 |
| 2.65142 | 3.161769 |
| 2.67037 | 3.161482 |
| 2.68945 | 3.161197 |
| 2.70867 | 3.160915 |
| 2.72803 | 3.160636 |
| 2.74753 | 3.160361 |
| 2.76717 | 3.160088 |
| 2.78695 | 3.159817 |
| 2.80686 | 3.15955 |
| 2.82693 | 3.159285 |
| 2.84713 | 3.159022 |
| 2.86748 | 3.158762 |
| 2.88797 | 3.158505 |
| 2.90861 | 3.15825 |
| 2.9294 | 3.157997 |
| 2.95034 | 3.157747 |
| 2.97143 | 3.157499 |
| 2.99266 | 3.157253 |
| 3.01405 | 3.157009 |
| 3.03559 | 3.156767 |
| 3.05729 | 3.156528 |
| 3.07914 | 3.15629 |
| 3.10115 | 3.156054 |
| 3.12331 | 3.15582 |
| 3.14564 | 3.155588 |
| 3.16812 | 3.155358 |
| 3.19076 | 3.155129 |
| 3.21357 | 3.154902 |
| 3.23653 | 3.154677 |
| 3.25967 | 3.154453 |
| 3.28296 | 3.154231 |
| 3.30643 | 3.15401 |
| 3.33006 | 3.15379 |
| 3.35386 | 3.153572 |
| 3.37783 | 3.153356 |
| 3.40197 | 3.15314 |
| 3.42629 | 3.152926 |
| 3.45078 | 3.152713 |
| 3.47544 | 3.152501 |
| 3.50028 | 3.15229 |
| 3.5253 | 3.152081 |
| 3.55049 | 3.151872 |
| 3.57587 | 3.151664 |
| 3.60142 | 3.151457 |
| 3.62716 | 3.151251 |
| 3.65309 | 3.151046 |
| 3.6792 | 3.150842 |
| 3.70549 | 3.150638 |
| 3.73198 | 3.150435 |
| 3.75865 | 3.150233 |
| 3.78551 | 3.150031 |
| 3.81257 | 3.14983 |
| 3.83982 | 3.149629 |
| 3.86726 | 3.149429 |
| 3.8949 | 3.149229 |
| 3.92274 | 3.14903 |
| 3.95078 | 3.148831 |
| 3.97901 | 3.148632 |
| 4.00745 | 3.148434 |
| 4.03609 | 3.148236 |
| 4.06494 | 3.148037 |
| 4.09399 | 3.147839 |
| 4.12325 | 3.147642 |
| 4.15272 | 3.147444 |
| 4.1824 | 3.147246 |
| 4.2123 | 3.147048 |
| 4.2424 | 3.14685 |
| 4.27272 | 3.146652 |
| 4.30326 | 3.146453 |
| 4.33402 | 3.146255 |
| 4.36499 | 3.146056 |
| 4.39619 | 3.145856 |
| 4.42761 | 3.145657 |
| 4.45926 | 3.145457 |
| 4.49113 | 3.145257 |
| 4.52323 | 3.145056 |
| 4.55556 | 3.144854 |
| 4.58812 | 3.144652 |
| 4.62091 | 3.14445 |
| 4.65393 | 3.144246 |
| 4.6872 | 3.144042 |
| 4.7207 | 3.143837 |
| 4.75444 | 3.143632 |
| 4.78842 | 3.143425 |
| 4.82264 | 3.143218 |
| 4.85711 | 3.143009 |
| 4.89182 | 3.1428 |
| 4.92679 | 3.14259 |
| 4.962 | 3.142378 |
| 4.99746 | 3.142165 |
| 5.03318 | 3.141952 |
| 5.06915 | 3.141737 |
| 5.10538 | 3.14152 |
| 5.14187 | 3.141302 |
| 5.17862 | 3.141083 |
| 5.21564 | 3.140863 |
| 5.25291 | 3.140641 |
| 5.29046 | 3.140417 |
| 5.32827 | 3.140192 |
| 5.36635 | 3.139965 |
| 5.4047 | 3.139736 |
| 5.44333 | 3.139506 |
| 5.48224 | 3.139274 |
| 5.52142 | 3.13904 |
| 5.56088 | 3.138804 |
| 5.60063 | 3.138566 |
| 5.64066 | 3.138326 |
| 5.68097 | 3.138084 |
| 5.72157 | 3.137839 |
| 5.76247 | 3.137593 |
| 5.80365 | 3.137344 |
| 5.84513 | 3.137093 |
| 5.88691 | 3.136839 |
| 5.92898 | 3.136583 |
| 5.97136 | 3.136325 |
| 6.01404 | 3.136064 |
| 6.05702 | 3.1358 |
| 6.10031 | 3.135533 |
| 6.14391 | 3.135264 |
| 6.18782 | 3.134992 |
| 6.23205 | 3.134717 |
| 6.27659 | 3.134439 |
| 6.32145 | 3.134158 |
| 6.36663 | 3.133873 |
| 6.41213 | 3.133586 |
| 6.45796 | 3.133295 |
| 6.50412 | 3.133001 |
| 6.5506 | 3.132703 |
| 6.59742 | 3.132402 |
| 6.64457 | 3.132098 |
| 6.69206 | 3.131789 |
| 6.73989 | 3.131477 |
| 6.78807 | 3.131161 |
| 6.83658 | 3.130841 |
| 6.88544 | 3.130517 |
| 6.93465 | 3.130189 |
| 6.98422 | 3.129857 |
| 7.03414 | 3.12952 |
| 7.08441 | 3.129179 |
| 7.13504 | 3.128834 |
| 7.18604 | 3.128484 |
| 7.2374 | 3.12813 |
| 7.28913 | 3.12777 |
| 7.34122 | 3.127406 |
| 7.39369 | 3.127037 |
| 7.44654 | 3.126663 |
| 7.49976 | 3.126283 |
| 7.55336 | 3.125899 |
| 7.60734 | 3.125509 |
| 7.66172 | 3.125113 |
| 7.71647 | 3.124712 |
| 7.77163 | 3.124305 |
| 7.82717 | 3.123892 |
| 7.88311 | 3.123473 |
| 7.93946 | 3.123049 |
| 7.9962 | 3.122617 |
| 8.05335 | 3.12218 |
| 8.11091 | 3.121736 |
| 8.16888 | 3.121285 |
| 8.22726 | 3.120828 |
| 8.28607 | 3.120364 |
| 8.34529 | 3.119892 |
| 8.40493 | 3.119414 |
| 8.465 | 3.118928 |
| 8.5255 | 3.118434 |
| 8.58644 | 3.117933 |
| 8.64781 | 3.117424 |
| 8.70961 | 3.116907 |
| 8.77186 | 3.116382 |
| 8.83456 | 3.115849 |
| 8.8977 | 3.115307 |
| 8.96129 | 3.114756 |
| 9.02534 | 3.114196 |
| 9.08985 | 3.113628 |
| 9.15481 | 3.11305 |
| 9.22024 | 3.112462 |
| 9.28614 | 3.111865 |
| 9.35251 | 3.111258 |
| 9.41936 | 3.110641 |
| 9.48668 | 3.110014 |
| 9.55448 | 3.109376 |
| 9.62277 | 3.108728 |
| 9.69155 | 3.108068 |
| 9.76081 | 3.107397 |
| 9.83057 | 3.106715 |
| 9.90084 | 3.106021 |
| 9.9716 | 3.105315 |
| 10.0429 | 3.104596 |
| 10.1146 | 3.103865 |
| 10.1869 | 3.103122 |
| 10.2597 | 3.102365 |
| 10.3331 | 3.101594 |
| 10.4069 | 3.10081 |
| 10.4813 | 3.100012 |
| 10.5562 | 3.0992 |
| 10.6317 | 3.098373 |
| 10.7077 | 3.097531 |
| 10.7842 | 3.096673 |
| 10.8613 | 3.0958 |
| 10.9389 | 3.094911 |
| 11.0171 | 3.094005 |
| 11.0958 | 3.093082 |
| 11.1751 | 3.092142 |
| 11.255 | 3.091185 |
| 11.3354 | 3.090209 |
| 11.4164 | 3.089214 |
| 11.498 | 3.088201 |
| 11.5802 | 3.087168 |
| 11.663 | 3.086115 |
| 11.7463 | 3.085042 |
| 11.8303 | 3.083948 |
| 11.9148 | 3.082832 |
| 12 | 3.081694 |
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.