Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(o) 0.7–12 µm; 100 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 100 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
- 3.10818
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.66076
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0111711 µm⁻¹
- Group index ng
- 3.14057
- Group velocity dispersion
- 367.785 fs²/mm
- Dispersion parameter D
- -82.3757 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; 100 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-100K-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_9fdb111a30e9/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-1998-100k-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_9fdb111a30e9/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 | 3.4933853 |
| C2 | 5.10900476 |
| C3 | 0.12778958 |
| C4 | 2.16855561 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 100 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 | 3.376935 |
| 0.705003 | 3.371848 |
| 0.710042 | 3.366875 |
| 0.715117 | 3.362012 |
| 0.720228 | 3.357256 |
| 0.725375 | 3.352604 |
| 0.73056 | 3.348053 |
| 0.735781 | 3.343601 |
| 0.74104 | 3.339245 |
| 0.746336 | 3.334981 |
| 0.75167 | 3.330808 |
| 0.757043 | 3.326722 |
| 0.762453 | 3.322723 |
| 0.767903 | 3.318806 |
| 0.773391 | 3.314971 |
| 0.778919 | 3.311215 |
| 0.784486 | 3.307535 |
| 0.790093 | 3.303931 |
| 0.79574 | 3.300399 |
| 0.801427 | 3.296939 |
| 0.807155 | 3.293548 |
| 0.812924 | 3.290225 |
| 0.818734 | 3.286968 |
| 0.824585 | 3.283775 |
| 0.830479 | 3.280644 |
| 0.836414 | 3.277575 |
| 0.842392 | 3.274565 |
| 0.848413 | 3.271614 |
| 0.854477 | 3.26872 |
| 0.860584 | 3.265881 |
| 0.866735 | 3.263096 |
| 0.87293 | 3.260364 |
| 0.879169 | 3.257684 |
| 0.885452 | 3.255055 |
| 0.891781 | 3.252475 |
| 0.898154 | 3.249943 |
| 0.904574 | 3.247458 |
| 0.911039 | 3.245019 |
| 0.91755 | 3.242625 |
| 0.924108 | 3.240275 |
| 0.930713 | 3.237968 |
| 0.937365 | 3.235703 |
| 0.944064 | 3.233479 |
| 0.950812 | 3.231296 |
| 0.957607 | 3.229152 |
| 0.964451 | 3.227046 |
| 0.971345 | 3.224978 |
| 0.978287 | 3.222947 |
| 0.985279 | 3.220952 |
| 0.992321 | 3.218992 |
| 0.999413 | 3.217067 |
| 1.00656 | 3.215176 |
| 1.01375 | 3.213318 |
| 1.021 | 3.211492 |
| 1.02829 | 3.209698 |
| 1.03564 | 3.207935 |
| 1.04304 | 3.206203 |
| 1.0505 | 3.204501 |
| 1.05801 | 3.202828 |
| 1.06557 | 3.201183 |
| 1.07318 | 3.199567 |
| 1.08085 | 3.197978 |
| 1.08858 | 3.196416 |
| 1.09636 | 3.19488 |
| 1.1042 | 3.193371 |
| 1.11209 | 3.191887 |
| 1.12004 | 3.190427 |
| 1.12804 | 3.188993 |
| 1.1361 | 3.187582 |
| 1.14422 | 3.186194 |
| 1.1524 | 3.18483 |
| 1.16064 | 3.183488 |
| 1.16893 | 3.182168 |
| 1.17729 | 3.18087 |
| 1.1857 | 3.179594 |
| 1.19418 | 3.178338 |
| 1.20271 | 3.177103 |
| 1.21131 | 3.175887 |
| 1.21997 | 3.174692 |
| 1.22868 | 3.173516 |
| 1.23747 | 3.172359 |
| 1.24631 | 3.171221 |
| 1.25522 | 3.1701 |
| 1.26419 | 3.168998 |
| 1.27322 | 3.167914 |
| 1.28232 | 3.166847 |
| 1.29149 | 3.165796 |
| 1.30072 | 3.164763 |
| 1.31002 | 3.163746 |
| 1.31938 | 3.162745 |
| 1.32881 | 3.161759 |
| 1.33831 | 3.16079 |
| 1.34787 | 3.159835 |
| 1.35751 | 3.158895 |
| 1.36721 | 3.15797 |
| 1.37698 | 3.15706 |
| 1.38682 | 3.156164 |
| 1.39673 | 3.155281 |
| 1.40672 | 3.154412 |
| 1.41677 | 3.153557 |
| 1.4269 | 3.152715 |
| 1.43709 | 3.151885 |
| 1.44736 | 3.151069 |
| 1.45771 | 3.150264 |
| 1.46813 | 3.149473 |
| 1.47862 | 3.148693 |
| 1.48919 | 3.147925 |
| 1.49983 | 3.147169 |
| 1.51055 | 3.146424 |
| 1.52135 | 3.14569 |
| 1.53222 | 3.144967 |
| 1.54317 | 3.144255 |
| 1.5542 | 3.143554 |
| 1.56531 | 3.142864 |
| 1.5765 | 3.142183 |
| 1.58776 | 3.141513 |
| 1.59911 | 3.140852 |
| 1.61054 | 3.140202 |
| 1.62205 | 3.139561 |
| 1.63365 | 3.138929 |
| 1.64532 | 3.138307 |
| 1.65708 | 3.137694 |
| 1.66892 | 3.137089 |
| 1.68085 | 3.136494 |
| 1.69287 | 3.135907 |
| 1.70497 | 3.135329 |
| 1.71715 | 3.134759 |
| 1.72942 | 3.134197 |
| 1.74178 | 3.133643 |
| 1.75423 | 3.133097 |
| 1.76677 | 3.132559 |
| 1.7794 | 3.132029 |
| 1.79212 | 3.131506 |
| 1.80492 | 3.13099 |
| 1.81782 | 3.130482 |
| 1.83082 | 3.129981 |
| 1.8439 | 3.129487 |
| 1.85708 | 3.129 |
| 1.87035 | 3.12852 |
| 1.88372 | 3.128046 |
| 1.89719 | 3.127579 |
| 1.91074 | 3.127118 |
| 1.9244 | 3.126664 |
| 1.93816 | 3.126216 |
| 1.95201 | 3.125773 |
| 1.96596 | 3.125337 |
| 1.98001 | 3.124907 |
| 1.99416 | 3.124483 |
| 2.00841 | 3.124064 |
| 2.02277 | 3.123651 |
| 2.03723 | 3.123244 |
| 2.05179 | 3.122841 |
| 2.06645 | 3.122444 |
| 2.08122 | 3.122053 |
| 2.09609 | 3.121666 |
| 2.11108 | 3.121285 |
| 2.12616 | 3.120908 |
| 2.14136 | 3.120536 |
| 2.15666 | 3.120169 |
| 2.17208 | 3.119807 |
| 2.1876 | 3.11945 |
| 2.20324 | 3.119096 |
| 2.21899 | 3.118748 |
| 2.23484 | 3.118403 |
| 2.25082 | 3.118063 |
| 2.2669 | 3.117727 |
| 2.28311 | 3.117396 |
| 2.29942 | 3.117068 |
| 2.31586 | 3.116744 |
| 2.33241 | 3.116424 |
| 2.34908 | 3.116108 |
| 2.36587 | 3.115796 |
| 2.38278 | 3.115487 |
| 2.39981 | 3.115182 |
| 2.41696 | 3.114881 |
| 2.43424 | 3.114583 |
| 2.45163 | 3.114288 |
| 2.46916 | 3.113997 |
| 2.4868 | 3.113709 |
| 2.50458 | 3.113425 |
| 2.52248 | 3.113143 |
| 2.54051 | 3.112865 |
| 2.55866 | 3.112589 |
| 2.57695 | 3.112317 |
| 2.59537 | 3.112047 |
| 2.61392 | 3.11178 |
| 2.6326 | 3.111516 |
| 2.65142 | 3.111255 |
| 2.67037 | 3.110996 |
| 2.68945 | 3.11074 |
| 2.70867 | 3.110487 |
| 2.72803 | 3.110236 |
| 2.74753 | 3.109988 |
| 2.76717 | 3.109741 |
| 2.78695 | 3.109498 |
| 2.80686 | 3.109256 |
| 2.82693 | 3.109017 |
| 2.84713 | 3.10878 |
| 2.86748 | 3.108545 |
| 2.88797 | 3.108312 |
| 2.90861 | 3.108081 |
| 2.9294 | 3.107852 |
| 2.95034 | 3.107625 |
| 2.97143 | 3.1074 |
| 2.99266 | 3.107177 |
| 3.01405 | 3.106955 |
| 3.03559 | 3.106735 |
| 3.05729 | 3.106517 |
| 3.07914 | 3.106301 |
| 3.10115 | 3.106086 |
| 3.12331 | 3.105872 |
| 3.14564 | 3.10566 |
| 3.16812 | 3.10545 |
| 3.19076 | 3.105241 |
| 3.21357 | 3.105033 |
| 3.23653 | 3.104827 |
| 3.25967 | 3.104622 |
| 3.28296 | 3.104418 |
| 3.30643 | 3.104215 |
| 3.33006 | 3.104013 |
| 3.35386 | 3.103813 |
| 3.37783 | 3.103613 |
| 3.40197 | 3.103415 |
| 3.42629 | 3.103217 |
| 3.45078 | 3.10302 |
| 3.47544 | 3.102825 |
| 3.50028 | 3.10263 |
| 3.5253 | 3.102435 |
| 3.55049 | 3.102242 |
| 3.57587 | 3.102049 |
| 3.60142 | 3.101857 |
| 3.62716 | 3.101666 |
| 3.65309 | 3.101475 |
| 3.6792 | 3.101285 |
| 3.70549 | 3.101095 |
| 3.73198 | 3.100905 |
| 3.75865 | 3.100716 |
| 3.78551 | 3.100528 |
| 3.81257 | 3.10034 |
| 3.83982 | 3.100152 |
| 3.86726 | 3.099964 |
| 3.8949 | 3.099776 |
| 3.92274 | 3.099589 |
| 3.95078 | 3.099402 |
| 3.97901 | 3.099214 |
| 4.00745 | 3.099027 |
| 4.03609 | 3.09884 |
| 4.06494 | 3.098653 |
| 4.09399 | 3.098466 |
| 4.12325 | 3.098278 |
| 4.15272 | 3.098091 |
| 4.1824 | 3.097903 |
| 4.2123 | 3.097715 |
| 4.2424 | 3.097527 |
| 4.27272 | 3.097338 |
| 4.30326 | 3.097149 |
| 4.33402 | 3.09696 |
| 4.36499 | 3.09677 |
| 4.39619 | 3.09658 |
| 4.42761 | 3.096389 |
| 4.45926 | 3.096198 |
| 4.49113 | 3.096006 |
| 4.52323 | 3.095813 |
| 4.55556 | 3.095619 |
| 4.58812 | 3.095425 |
| 4.62091 | 3.09523 |
| 4.65393 | 3.095034 |
| 4.6872 | 3.094838 |
| 4.7207 | 3.09464 |
| 4.75444 | 3.094441 |
| 4.78842 | 3.094242 |
| 4.82264 | 3.094041 |
| 4.85711 | 3.093839 |
| 4.89182 | 3.093636 |
| 4.92679 | 3.093432 |
| 4.962 | 3.093227 |
| 4.99746 | 3.09302 |
| 5.03318 | 3.092812 |
| 5.06915 | 3.092602 |
| 5.10538 | 3.092391 |
| 5.14187 | 3.092179 |
| 5.17862 | 3.091965 |
| 5.21564 | 3.09175 |
| 5.25291 | 3.091532 |
| 5.29046 | 3.091314 |
| 5.32827 | 3.091093 |
| 5.36635 | 3.09087 |
| 5.4047 | 3.090646 |
| 5.44333 | 3.09042 |
| 5.48224 | 3.090192 |
| 5.52142 | 3.089962 |
| 5.56088 | 3.08973 |
| 5.60063 | 3.089495 |
| 5.64066 | 3.089259 |
| 5.68097 | 3.08902 |
| 5.72157 | 3.088779 |
| 5.76247 | 3.088536 |
| 5.80365 | 3.08829 |
| 5.84513 | 3.088042 |
| 5.88691 | 3.087791 |
| 5.92898 | 3.087537 |
| 5.97136 | 3.087281 |
| 6.01404 | 3.087022 |
| 6.05702 | 3.086761 |
| 6.10031 | 3.086496 |
| 6.14391 | 3.086229 |
| 6.18782 | 3.085959 |
| 6.23205 | 3.085685 |
| 6.27659 | 3.085409 |
| 6.32145 | 3.085129 |
| 6.36663 | 3.084846 |
| 6.41213 | 3.08456 |
| 6.45796 | 3.08427 |
| 6.50412 | 3.083977 |
| 6.5506 | 3.08368 |
| 6.59742 | 3.083379 |
| 6.64457 | 3.083075 |
| 6.69206 | 3.082767 |
| 6.73989 | 3.082455 |
| 6.78807 | 3.082139 |
| 6.83658 | 3.081819 |
| 6.88544 | 3.081495 |
| 6.93465 | 3.081167 |
| 6.98422 | 3.080834 |
| 7.03414 | 3.080497 |
| 7.08441 | 3.080156 |
| 7.13504 | 3.07981 |
| 7.18604 | 3.079459 |
| 7.2374 | 3.079103 |
| 7.28913 | 3.078743 |
| 7.34122 | 3.078377 |
| 7.39369 | 3.078006 |
| 7.44654 | 3.077631 |
| 7.49976 | 3.077249 |
| 7.55336 | 3.076863 |
| 7.60734 | 3.076471 |
| 7.66172 | 3.076073 |
| 7.71647 | 3.075669 |
| 7.77163 | 3.07526 |
| 7.82717 | 3.074845 |
| 7.88311 | 3.074423 |
| 7.93946 | 3.073995 |
| 7.9962 | 3.073561 |
| 8.05335 | 3.07312 |
| 8.11091 | 3.072673 |
| 8.16888 | 3.072219 |
| 8.22726 | 3.071758 |
| 8.28607 | 3.07129 |
| 8.34529 | 3.070814 |
| 8.40493 | 3.070332 |
| 8.465 | 3.069841 |
| 8.5255 | 3.069343 |
| 8.58644 | 3.068838 |
| 8.64781 | 3.068324 |
| 8.70961 | 3.067802 |
| 8.77186 | 3.067272 |
| 8.83456 | 3.066733 |
| 8.8977 | 3.066185 |
| 8.96129 | 3.065629 |
| 9.02534 | 3.065064 |
| 9.08985 | 3.064489 |
| 9.15481 | 3.063905 |
| 9.22024 | 3.063311 |
| 9.28614 | 3.062707 |
| 9.35251 | 3.062094 |
| 9.41936 | 3.06147 |
| 9.48668 | 3.060835 |
| 9.55448 | 3.06019 |
| 9.62277 | 3.059534 |
| 9.69155 | 3.058866 |
| 9.76081 | 3.058188 |
| 9.83057 | 3.057497 |
| 9.90084 | 3.056795 |
| 9.9716 | 3.05608 |
| 10.0429 | 3.055353 |
| 10.1146 | 3.054612 |
| 10.1869 | 3.053859 |
| 10.2597 | 3.053093 |
| 10.3331 | 3.052313 |
| 10.4069 | 3.051519 |
| 10.4813 | 3.05071 |
| 10.5562 | 3.049887 |
| 10.6317 | 3.049049 |
| 10.7077 | 3.048196 |
| 10.7842 | 3.047327 |
| 10.8613 | 3.046442 |
| 10.9389 | 3.045541 |
| 11.0171 | 3.044623 |
| 11.0958 | 3.043688 |
| 11.1751 | 3.042735 |
| 11.255 | 3.041764 |
| 11.3354 | 3.040775 |
| 11.4164 | 3.039767 |
| 11.498 | 3.038739 |
| 11.5802 | 3.037692 |
| 11.663 | 3.036624 |
| 11.7463 | 3.035535 |
| 11.8303 | 3.034425 |
| 11.9148 | 3.033294 |
| 12 | 3.032139 |
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.