Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(e) 0.7–12 µm; 450 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 450 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
- 3.19918
- Extinction coefficient k
- 0
- Permittivity ε1
- 10.2348
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.012894 µm⁻¹
- Group index ng
- 3.23657
- Group velocity dispersion
- 456.361 fs²/mm
- Dispersion parameter D
- -102.215 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; 450 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-450K-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_d6eddb60b51d/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-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_d6eddb60b51d/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 | 4.05767976 |
| C2 | 5.09918075 |
| C3 | 0.15816346 |
| C4 | 2.10218698 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 450 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 | 3.547695 |
| 0.705003 | 3.54058 |
| 0.710042 | 3.533645 |
| 0.715117 | 3.526883 |
| 0.720228 | 3.520288 |
| 0.725375 | 3.513856 |
| 0.73056 | 3.50758 |
| 0.735781 | 3.501456 |
| 0.74104 | 3.495479 |
| 0.746336 | 3.489643 |
| 0.75167 | 3.483946 |
| 0.757043 | 3.478381 |
| 0.762453 | 3.472946 |
| 0.767903 | 3.467637 |
| 0.773391 | 3.462448 |
| 0.778919 | 3.457378 |
| 0.784486 | 3.452422 |
| 0.790093 | 3.447577 |
| 0.79574 | 3.44284 |
| 0.801427 | 3.438208 |
| 0.807155 | 3.433677 |
| 0.812924 | 3.429245 |
| 0.818734 | 3.424909 |
| 0.824585 | 3.420666 |
| 0.830479 | 3.416514 |
| 0.836414 | 3.41245 |
| 0.842392 | 3.408473 |
| 0.848413 | 3.404578 |
| 0.854477 | 3.400766 |
| 0.860584 | 3.397032 |
| 0.866735 | 3.393375 |
| 0.87293 | 3.389793 |
| 0.879169 | 3.386285 |
| 0.885452 | 3.382847 |
| 0.891781 | 3.37948 |
| 0.898154 | 3.376179 |
| 0.904574 | 3.372945 |
| 0.911039 | 3.369775 |
| 0.91755 | 3.366667 |
| 0.924108 | 3.363621 |
| 0.930713 | 3.360635 |
| 0.937365 | 3.357706 |
| 0.944064 | 3.354834 |
| 0.950812 | 3.352018 |
| 0.957607 | 3.349256 |
| 0.964451 | 3.346547 |
| 0.971345 | 3.343889 |
| 0.978287 | 3.341282 |
| 0.985279 | 3.338724 |
| 0.992321 | 3.336214 |
| 0.999413 | 3.33375 |
| 1.00656 | 3.331333 |
| 1.01375 | 3.328961 |
| 1.021 | 3.326632 |
| 1.02829 | 3.324346 |
| 1.03564 | 3.322102 |
| 1.04304 | 3.319899 |
| 1.0505 | 3.317737 |
| 1.05801 | 3.315613 |
| 1.06557 | 3.313527 |
| 1.07318 | 3.31148 |
| 1.08085 | 3.309468 |
| 1.08858 | 3.307493 |
| 1.09636 | 3.305553 |
| 1.1042 | 3.303647 |
| 1.11209 | 3.301775 |
| 1.12004 | 3.299935 |
| 1.12804 | 3.298128 |
| 1.1361 | 3.296353 |
| 1.14422 | 3.294609 |
| 1.1524 | 3.292894 |
| 1.16064 | 3.29121 |
| 1.16893 | 3.289554 |
| 1.17729 | 3.287927 |
| 1.1857 | 3.286328 |
| 1.19418 | 3.284756 |
| 1.20271 | 3.283211 |
| 1.21131 | 3.281692 |
| 1.21997 | 3.280199 |
| 1.22868 | 3.278731 |
| 1.23747 | 3.277287 |
| 1.24631 | 3.275868 |
| 1.25522 | 3.274473 |
| 1.26419 | 3.273101 |
| 1.27322 | 3.271752 |
| 1.28232 | 3.270425 |
| 1.29149 | 3.26912 |
| 1.30072 | 3.267836 |
| 1.31002 | 3.266574 |
| 1.31938 | 3.265332 |
| 1.32881 | 3.264111 |
| 1.33831 | 3.262909 |
| 1.34787 | 3.261727 |
| 1.35751 | 3.260565 |
| 1.36721 | 3.259421 |
| 1.37698 | 3.258295 |
| 1.38682 | 3.257188 |
| 1.39673 | 3.256098 |
| 1.40672 | 3.255026 |
| 1.41677 | 3.253971 |
| 1.4269 | 3.252933 |
| 1.43709 | 3.251911 |
| 1.44736 | 3.250906 |
| 1.45771 | 3.249916 |
| 1.46813 | 3.248942 |
| 1.47862 | 3.247983 |
| 1.48919 | 3.24704 |
| 1.49983 | 3.246111 |
| 1.51055 | 3.245196 |
| 1.52135 | 3.244296 |
| 1.53222 | 3.24341 |
| 1.54317 | 3.242537 |
| 1.5542 | 3.241678 |
| 1.56531 | 3.240832 |
| 1.5765 | 3.24 |
| 1.58776 | 3.23918 |
| 1.59911 | 3.238372 |
| 1.61054 | 3.237577 |
| 1.62205 | 3.236794 |
| 1.63365 | 3.236023 |
| 1.64532 | 3.235263 |
| 1.65708 | 3.234515 |
| 1.66892 | 3.233778 |
| 1.68085 | 3.233053 |
| 1.69287 | 3.232338 |
| 1.70497 | 3.231634 |
| 1.71715 | 3.23094 |
| 1.72942 | 3.230257 |
| 1.74178 | 3.229584 |
| 1.75423 | 3.22892 |
| 1.76677 | 3.228267 |
| 1.7794 | 3.227623 |
| 1.79212 | 3.226989 |
| 1.80492 | 3.226363 |
| 1.81782 | 3.225747 |
| 1.83082 | 3.22514 |
| 1.8439 | 3.224542 |
| 1.85708 | 3.223952 |
| 1.87035 | 3.223371 |
| 1.88372 | 3.222798 |
| 1.89719 | 3.222234 |
| 1.91074 | 3.221677 |
| 1.9244 | 3.221129 |
| 1.93816 | 3.220588 |
| 1.95201 | 3.220055 |
| 1.96596 | 3.219529 |
| 1.98001 | 3.219011 |
| 1.99416 | 3.2185 |
| 2.00841 | 3.217996 |
| 2.02277 | 3.217499 |
| 2.03723 | 3.217009 |
| 2.05179 | 3.216525 |
| 2.06645 | 3.216049 |
| 2.08122 | 3.215579 |
| 2.09609 | 3.215115 |
| 2.11108 | 3.214658 |
| 2.12616 | 3.214207 |
| 2.14136 | 3.213762 |
| 2.15666 | 3.213322 |
| 2.17208 | 3.212889 |
| 2.1876 | 3.212462 |
| 2.20324 | 3.21204 |
| 2.21899 | 3.211624 |
| 2.23484 | 3.211213 |
| 2.25082 | 3.210807 |
| 2.2669 | 3.210407 |
| 2.28311 | 3.210012 |
| 2.29942 | 3.209622 |
| 2.31586 | 3.209237 |
| 2.33241 | 3.208857 |
| 2.34908 | 3.208482 |
| 2.36587 | 3.208112 |
| 2.38278 | 3.207746 |
| 2.39981 | 3.207385 |
| 2.41696 | 3.207028 |
| 2.43424 | 3.206676 |
| 2.45163 | 3.206327 |
| 2.46916 | 3.205984 |
| 2.4868 | 3.205644 |
| 2.50458 | 3.205308 |
| 2.52248 | 3.204977 |
| 2.54051 | 3.204649 |
| 2.55866 | 3.204325 |
| 2.57695 | 3.204005 |
| 2.59537 | 3.203688 |
| 2.61392 | 3.203375 |
| 2.6326 | 3.203066 |
| 2.65142 | 3.20276 |
| 2.67037 | 3.202458 |
| 2.68945 | 3.202159 |
| 2.70867 | 3.201863 |
| 2.72803 | 3.201571 |
| 2.74753 | 3.201281 |
| 2.76717 | 3.200995 |
| 2.78695 | 3.200712 |
| 2.80686 | 3.200431 |
| 2.82693 | 3.200154 |
| 2.84713 | 3.199879 |
| 2.86748 | 3.199607 |
| 2.88797 | 3.199338 |
| 2.90861 | 3.199072 |
| 2.9294 | 3.198808 |
| 2.95034 | 3.198546 |
| 2.97143 | 3.198287 |
| 2.99266 | 3.198031 |
| 3.01405 | 3.197777 |
| 3.03559 | 3.197525 |
| 3.05729 | 3.197275 |
| 3.07914 | 3.197028 |
| 3.10115 | 3.196782 |
| 3.12331 | 3.196539 |
| 3.14564 | 3.196298 |
| 3.16812 | 3.196059 |
| 3.19076 | 3.195822 |
| 3.21357 | 3.195586 |
| 3.23653 | 3.195352 |
| 3.25967 | 3.195121 |
| 3.28296 | 3.19489 |
| 3.30643 | 3.194662 |
| 3.33006 | 3.194435 |
| 3.35386 | 3.19421 |
| 3.37783 | 3.193986 |
| 3.40197 | 3.193764 |
| 3.42629 | 3.193543 |
| 3.45078 | 3.193323 |
| 3.47544 | 3.193105 |
| 3.50028 | 3.192888 |
| 3.5253 | 3.192673 |
| 3.55049 | 3.192458 |
| 3.57587 | 3.192245 |
| 3.60142 | 3.192032 |
| 3.62716 | 3.191821 |
| 3.65309 | 3.191611 |
| 3.6792 | 3.191402 |
| 3.70549 | 3.191193 |
| 3.73198 | 3.190986 |
| 3.75865 | 3.190779 |
| 3.78551 | 3.190573 |
| 3.81257 | 3.190368 |
| 3.83982 | 3.190163 |
| 3.86726 | 3.189959 |
| 3.8949 | 3.189756 |
| 3.92274 | 3.189553 |
| 3.95078 | 3.189351 |
| 3.97901 | 3.189149 |
| 4.00745 | 3.188947 |
| 4.03609 | 3.188746 |
| 4.06494 | 3.188546 |
| 4.09399 | 3.188345 |
| 4.12325 | 3.188145 |
| 4.15272 | 3.187945 |
| 4.1824 | 3.187745 |
| 4.2123 | 3.187545 |
| 4.2424 | 3.187346 |
| 4.27272 | 3.187146 |
| 4.30326 | 3.186946 |
| 4.33402 | 3.186746 |
| 4.36499 | 3.186546 |
| 4.39619 | 3.186346 |
| 4.42761 | 3.186146 |
| 4.45926 | 3.185945 |
| 4.49113 | 3.185745 |
| 4.52323 | 3.185543 |
| 4.55556 | 3.185342 |
| 4.58812 | 3.18514 |
| 4.62091 | 3.184937 |
| 4.65393 | 3.184734 |
| 4.6872 | 3.184531 |
| 4.7207 | 3.184327 |
| 4.75444 | 3.184122 |
| 4.78842 | 3.183916 |
| 4.82264 | 3.18371 |
| 4.85711 | 3.183503 |
| 4.89182 | 3.183295 |
| 4.92679 | 3.183086 |
| 4.962 | 3.182876 |
| 4.99746 | 3.182665 |
| 5.03318 | 3.182454 |
| 5.06915 | 3.182241 |
| 5.10538 | 3.182027 |
| 5.14187 | 3.181812 |
| 5.17862 | 3.181595 |
| 5.21564 | 3.181377 |
| 5.25291 | 3.181158 |
| 5.29046 | 3.180938 |
| 5.32827 | 3.180716 |
| 5.36635 | 3.180493 |
| 5.4047 | 3.180268 |
| 5.44333 | 3.180041 |
| 5.48224 | 3.179813 |
| 5.52142 | 3.179583 |
| 5.56088 | 3.179351 |
| 5.60063 | 3.179118 |
| 5.64066 | 3.178883 |
| 5.68097 | 3.178645 |
| 5.72157 | 3.178406 |
| 5.76247 | 3.178165 |
| 5.80365 | 3.177921 |
| 5.84513 | 3.177676 |
| 5.88691 | 3.177428 |
| 5.92898 | 3.177178 |
| 5.97136 | 3.176926 |
| 6.01404 | 3.176671 |
| 6.05702 | 3.176414 |
| 6.10031 | 3.176154 |
| 6.14391 | 3.175891 |
| 6.18782 | 3.175626 |
| 6.23205 | 3.175359 |
| 6.27659 | 3.175088 |
| 6.32145 | 3.174815 |
| 6.36663 | 3.174538 |
| 6.41213 | 3.174259 |
| 6.45796 | 3.173976 |
| 6.50412 | 3.173691 |
| 6.5506 | 3.173402 |
| 6.59742 | 3.17311 |
| 6.64457 | 3.172814 |
| 6.69206 | 3.172515 |
| 6.73989 | 3.172212 |
| 6.78807 | 3.171906 |
| 6.83658 | 3.171596 |
| 6.88544 | 3.171283 |
| 6.93465 | 3.170965 |
| 6.98422 | 3.170644 |
| 7.03414 | 3.170318 |
| 7.08441 | 3.169989 |
| 7.13504 | 3.169655 |
| 7.18604 | 3.169317 |
| 7.2374 | 3.168974 |
| 7.28913 | 3.168627 |
| 7.34122 | 3.168275 |
| 7.39369 | 3.167919 |
| 7.44654 | 3.167558 |
| 7.49976 | 3.167192 |
| 7.55336 | 3.166821 |
| 7.60734 | 3.166445 |
| 7.66172 | 3.166063 |
| 7.71647 | 3.165676 |
| 7.77163 | 3.165284 |
| 7.82717 | 3.164887 |
| 7.88311 | 3.164483 |
| 7.93946 | 3.164074 |
| 7.9962 | 3.163659 |
| 8.05335 | 3.163238 |
| 8.11091 | 3.16281 |
| 8.16888 | 3.162377 |
| 8.22726 | 3.161937 |
| 8.28607 | 3.16149 |
| 8.34529 | 3.161037 |
| 8.40493 | 3.160576 |
| 8.465 | 3.160109 |
| 8.5255 | 3.159635 |
| 8.58644 | 3.159153 |
| 8.64781 | 3.158664 |
| 8.70961 | 3.158167 |
| 8.77186 | 3.157663 |
| 8.83456 | 3.15715 |
| 8.8977 | 3.15663 |
| 8.96129 | 3.156101 |
| 9.02534 | 3.155564 |
| 9.08985 | 3.155018 |
| 9.15481 | 3.154463 |
| 9.22024 | 3.153899 |
| 9.28614 | 3.153327 |
| 9.35251 | 3.152744 |
| 9.41936 | 3.152152 |
| 9.48668 | 3.15155 |
| 9.55448 | 3.150939 |
| 9.62277 | 3.150316 |
| 9.69155 | 3.149684 |
| 9.76081 | 3.149041 |
| 9.83057 | 3.148386 |
| 9.90084 | 3.147721 |
| 9.9716 | 3.147044 |
| 10.0429 | 3.146356 |
| 10.1146 | 3.145655 |
| 10.1869 | 3.144942 |
| 10.2597 | 3.144217 |
| 10.3331 | 3.143479 |
| 10.4069 | 3.142728 |
| 10.4813 | 3.141963 |
| 10.5562 | 3.141185 |
| 10.6317 | 3.140393 |
| 10.7077 | 3.139586 |
| 10.7842 | 3.138765 |
| 10.8613 | 3.137929 |
| 10.9389 | 3.137078 |
| 11.0171 | 3.13621 |
| 11.0958 | 3.135327 |
| 11.1751 | 3.134427 |
| 11.255 | 3.13351 |
| 11.3354 | 3.132576 |
| 11.4164 | 3.131624 |
| 11.498 | 3.130655 |
| 11.5802 | 3.129666 |
| 11.663 | 3.128658 |
| 11.7463 | 3.127631 |
| 11.8303 | 3.126584 |
| 11.9148 | 3.125517 |
| 12 | 3.124428 |
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.