Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(e) 0.7–12 µm; 150 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 150 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
- 3.14924
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.91768
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0118423 µm⁻¹
- Group index ng
- 3.18358
- Group velocity dispersion
- 404.603 fs²/mm
- Dispersion parameter D
- -90.622 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; 150 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-150K-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_b2f7a4ef1f16/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-1998-150k-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_b2f7a4ef1f16/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 | 3.56209039 |
| C2 | 5.28876458 |
| C3 | 0.13562281 |
| C4 | 2.10527581 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 150 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 | 3.445832 |
| 0.705003 | 3.440113 |
| 0.710042 | 3.434525 |
| 0.715117 | 3.429064 |
| 0.720228 | 3.423728 |
| 0.725375 | 3.418512 |
| 0.73056 | 3.413412 |
| 0.735781 | 3.408425 |
| 0.74104 | 3.403549 |
| 0.746336 | 3.398779 |
| 0.75167 | 3.394113 |
| 0.757043 | 3.389548 |
| 0.762453 | 3.385081 |
| 0.767903 | 3.38071 |
| 0.773391 | 3.376431 |
| 0.778919 | 3.372243 |
| 0.784486 | 3.368142 |
| 0.790093 | 3.364127 |
| 0.79574 | 3.360195 |
| 0.801427 | 3.356344 |
| 0.807155 | 3.352572 |
| 0.812924 | 3.348876 |
| 0.818734 | 3.345256 |
| 0.824585 | 3.341709 |
| 0.830479 | 3.338232 |
| 0.836414 | 3.334825 |
| 0.842392 | 3.331486 |
| 0.848413 | 3.328213 |
| 0.854477 | 3.325004 |
| 0.860584 | 3.321858 |
| 0.866735 | 3.318773 |
| 0.87293 | 3.315747 |
| 0.879169 | 3.31278 |
| 0.885452 | 3.30987 |
| 0.891781 | 3.307016 |
| 0.898154 | 3.304216 |
| 0.904574 | 3.301468 |
| 0.911039 | 3.298773 |
| 0.91755 | 3.296128 |
| 0.924108 | 3.293533 |
| 0.930713 | 3.290986 |
| 0.937365 | 3.288486 |
| 0.944064 | 3.286032 |
| 0.950812 | 3.283623 |
| 0.957607 | 3.281259 |
| 0.964451 | 3.278937 |
| 0.971345 | 3.276658 |
| 0.978287 | 3.27442 |
| 0.985279 | 3.272223 |
| 0.992321 | 3.270064 |
| 0.999413 | 3.267945 |
| 1.00656 | 3.265863 |
| 1.01375 | 3.263818 |
| 1.021 | 3.26181 |
| 1.02829 | 3.259837 |
| 1.03564 | 3.257898 |
| 1.04304 | 3.255994 |
| 1.0505 | 3.254123 |
| 1.05801 | 3.252284 |
| 1.06557 | 3.250478 |
| 1.07318 | 3.248702 |
| 1.08085 | 3.246958 |
| 1.08858 | 3.245243 |
| 1.09636 | 3.243558 |
| 1.1042 | 3.241901 |
| 1.11209 | 3.240273 |
| 1.12004 | 3.238672 |
| 1.12804 | 3.237098 |
| 1.1361 | 3.235551 |
| 1.14422 | 3.23403 |
| 1.1524 | 3.232535 |
| 1.16064 | 3.231064 |
| 1.16893 | 3.229618 |
| 1.17729 | 3.228197 |
| 1.1857 | 3.226798 |
| 1.19418 | 3.225423 |
| 1.20271 | 3.224071 |
| 1.21131 | 3.222741 |
| 1.21997 | 3.221432 |
| 1.22868 | 3.220146 |
| 1.23747 | 3.21888 |
| 1.24631 | 3.217634 |
| 1.25522 | 3.216409 |
| 1.26419 | 3.215204 |
| 1.27322 | 3.214019 |
| 1.28232 | 3.212852 |
| 1.29149 | 3.211704 |
| 1.30072 | 3.210575 |
| 1.31002 | 3.209464 |
| 1.31938 | 3.20837 |
| 1.32881 | 3.207294 |
| 1.33831 | 3.206235 |
| 1.34787 | 3.205192 |
| 1.35751 | 3.204167 |
| 1.36721 | 3.203157 |
| 1.37698 | 3.202163 |
| 1.38682 | 3.201185 |
| 1.39673 | 3.200222 |
| 1.40672 | 3.199275 |
| 1.41677 | 3.198342 |
| 1.4269 | 3.197423 |
| 1.43709 | 3.196519 |
| 1.44736 | 3.195629 |
| 1.45771 | 3.194752 |
| 1.46813 | 3.193889 |
| 1.47862 | 3.193039 |
| 1.48919 | 3.192203 |
| 1.49983 | 3.191379 |
| 1.51055 | 3.190567 |
| 1.52135 | 3.189768 |
| 1.53222 | 3.188982 |
| 1.54317 | 3.188207 |
| 1.5542 | 3.187443 |
| 1.56531 | 3.186692 |
| 1.5765 | 3.185951 |
| 1.58776 | 3.185222 |
| 1.59911 | 3.184504 |
| 1.61054 | 3.183796 |
| 1.62205 | 3.183099 |
| 1.63365 | 3.182412 |
| 1.64532 | 3.181736 |
| 1.65708 | 3.181069 |
| 1.66892 | 3.180412 |
| 1.68085 | 3.179765 |
| 1.69287 | 3.179128 |
| 1.70497 | 3.178499 |
| 1.71715 | 3.17788 |
| 1.72942 | 3.17727 |
| 1.74178 | 3.176669 |
| 1.75423 | 3.176076 |
| 1.76677 | 3.175493 |
| 1.7794 | 3.174917 |
| 1.79212 | 3.17435 |
| 1.80492 | 3.173791 |
| 1.81782 | 3.173239 |
| 1.83082 | 3.172696 |
| 1.8439 | 3.17216 |
| 1.85708 | 3.171632 |
| 1.87035 | 3.171112 |
| 1.88372 | 3.170599 |
| 1.89719 | 3.170092 |
| 1.91074 | 3.169594 |
| 1.9244 | 3.169101 |
| 1.93816 | 3.168616 |
| 1.95201 | 3.168138 |
| 1.96596 | 3.167666 |
| 1.98001 | 3.1672 |
| 1.99416 | 3.166741 |
| 2.00841 | 3.166289 |
| 2.02277 | 3.165842 |
| 2.03723 | 3.165401 |
| 2.05179 | 3.164967 |
| 2.06645 | 3.164538 |
| 2.08122 | 3.164115 |
| 2.09609 | 3.163697 |
| 2.11108 | 3.163286 |
| 2.12616 | 3.162879 |
| 2.14136 | 3.162478 |
| 2.15666 | 3.162082 |
| 2.17208 | 3.161691 |
| 2.1876 | 3.161306 |
| 2.20324 | 3.160925 |
| 2.21899 | 3.160549 |
| 2.23484 | 3.160178 |
| 2.25082 | 3.159812 |
| 2.2669 | 3.159451 |
| 2.28311 | 3.159094 |
| 2.29942 | 3.158741 |
| 2.31586 | 3.158393 |
| 2.33241 | 3.158049 |
| 2.34908 | 3.157709 |
| 2.36587 | 3.157374 |
| 2.38278 | 3.157042 |
| 2.39981 | 3.156715 |
| 2.41696 | 3.156391 |
| 2.43424 | 3.156071 |
| 2.45163 | 3.155756 |
| 2.46916 | 3.155443 |
| 2.4868 | 3.155135 |
| 2.50458 | 3.15483 |
| 2.52248 | 3.154528 |
| 2.54051 | 3.15423 |
| 2.55866 | 3.153935 |
| 2.57695 | 3.153644 |
| 2.59537 | 3.153356 |
| 2.61392 | 3.153071 |
| 2.6326 | 3.152789 |
| 2.65142 | 3.15251 |
| 2.67037 | 3.152234 |
| 2.68945 | 3.151961 |
| 2.70867 | 3.151691 |
| 2.72803 | 3.151424 |
| 2.74753 | 3.151159 |
| 2.76717 | 3.150897 |
| 2.78695 | 3.150638 |
| 2.80686 | 3.150381 |
| 2.82693 | 3.150127 |
| 2.84713 | 3.149875 |
| 2.86748 | 3.149626 |
| 2.88797 | 3.149378 |
| 2.90861 | 3.149134 |
| 2.9294 | 3.148891 |
| 2.95034 | 3.148651 |
| 2.97143 | 3.148413 |
| 2.99266 | 3.148176 |
| 3.01405 | 3.147942 |
| 3.03559 | 3.14771 |
| 3.05729 | 3.14748 |
| 3.07914 | 3.147251 |
| 3.10115 | 3.147025 |
| 3.12331 | 3.1468 |
| 3.14564 | 3.146577 |
| 3.16812 | 3.146356 |
| 3.19076 | 3.146136 |
| 3.21357 | 3.145918 |
| 3.23653 | 3.145701 |
| 3.25967 | 3.145486 |
| 3.28296 | 3.145272 |
| 3.30643 | 3.14506 |
| 3.33006 | 3.144849 |
| 3.35386 | 3.144639 |
| 3.37783 | 3.144431 |
| 3.40197 | 3.144223 |
| 3.42629 | 3.144017 |
| 3.45078 | 3.143812 |
| 3.47544 | 3.143608 |
| 3.50028 | 3.143406 |
| 3.5253 | 3.143204 |
| 3.55049 | 3.143003 |
| 3.57587 | 3.142803 |
| 3.60142 | 3.142604 |
| 3.62716 | 3.142405 |
| 3.65309 | 3.142208 |
| 3.6792 | 3.142011 |
| 3.70549 | 3.141815 |
| 3.73198 | 3.141619 |
| 3.75865 | 3.141424 |
| 3.78551 | 3.14123 |
| 3.81257 | 3.141036 |
| 3.83982 | 3.140842 |
| 3.86726 | 3.140649 |
| 3.8949 | 3.140457 |
| 3.92274 | 3.140264 |
| 3.95078 | 3.140073 |
| 3.97901 | 3.139881 |
| 4.00745 | 3.139689 |
| 4.03609 | 3.139498 |
| 4.06494 | 3.139307 |
| 4.09399 | 3.139116 |
| 4.12325 | 3.138925 |
| 4.15272 | 3.138734 |
| 4.1824 | 3.138543 |
| 4.2123 | 3.138352 |
| 4.2424 | 3.13816 |
| 4.27272 | 3.137969 |
| 4.30326 | 3.137777 |
| 4.33402 | 3.137586 |
| 4.36499 | 3.137393 |
| 4.39619 | 3.137201 |
| 4.42761 | 3.137008 |
| 4.45926 | 3.136815 |
| 4.49113 | 3.136621 |
| 4.52323 | 3.136427 |
| 4.55556 | 3.136232 |
| 4.58812 | 3.136037 |
| 4.62091 | 3.135841 |
| 4.65393 | 3.135644 |
| 4.6872 | 3.135447 |
| 4.7207 | 3.135249 |
| 4.75444 | 3.13505 |
| 4.78842 | 3.13485 |
| 4.82264 | 3.13465 |
| 4.85711 | 3.134448 |
| 4.89182 | 3.134245 |
| 4.92679 | 3.134042 |
| 4.962 | 3.133837 |
| 4.99746 | 3.133631 |
| 5.03318 | 3.133424 |
| 5.06915 | 3.133216 |
| 5.10538 | 3.133006 |
| 5.14187 | 3.132795 |
| 5.17862 | 3.132583 |
| 5.21564 | 3.13237 |
| 5.25291 | 3.132154 |
| 5.29046 | 3.131938 |
| 5.32827 | 3.13172 |
| 5.36635 | 3.1315 |
| 5.4047 | 3.131278 |
| 5.44333 | 3.131055 |
| 5.48224 | 3.13083 |
| 5.52142 | 3.130603 |
| 5.56088 | 3.130374 |
| 5.60063 | 3.130144 |
| 5.64066 | 3.129911 |
| 5.68097 | 3.129676 |
| 5.72157 | 3.129439 |
| 5.76247 | 3.1292 |
| 5.80365 | 3.128959 |
| 5.84513 | 3.128715 |
| 5.88691 | 3.128469 |
| 5.92898 | 3.128221 |
| 5.97136 | 3.12797 |
| 6.01404 | 3.127717 |
| 6.05702 | 3.127461 |
| 6.10031 | 3.127202 |
| 6.14391 | 3.126941 |
| 6.18782 | 3.126677 |
| 6.23205 | 3.12641 |
| 6.27659 | 3.12614 |
| 6.32145 | 3.125867 |
| 6.36663 | 3.125591 |
| 6.41213 | 3.125312 |
| 6.45796 | 3.12503 |
| 6.50412 | 3.124744 |
| 6.5506 | 3.124456 |
| 6.59742 | 3.124163 |
| 6.64457 | 3.123867 |
| 6.69206 | 3.123568 |
| 6.73989 | 3.123265 |
| 6.78807 | 3.122958 |
| 6.83658 | 3.122647 |
| 6.88544 | 3.122333 |
| 6.93465 | 3.122014 |
| 6.98422 | 3.121691 |
| 7.03414 | 3.121365 |
| 7.08441 | 3.121034 |
| 7.13504 | 3.120698 |
| 7.18604 | 3.120358 |
| 7.2374 | 3.120014 |
| 7.28913 | 3.119665 |
| 7.34122 | 3.119311 |
| 7.39369 | 3.118952 |
| 7.44654 | 3.118589 |
| 7.49976 | 3.11822 |
| 7.55336 | 3.117846 |
| 7.60734 | 3.117467 |
| 7.66172 | 3.117083 |
| 7.71647 | 3.116693 |
| 7.77163 | 3.116298 |
| 7.82717 | 3.115896 |
| 7.88311 | 3.11549 |
| 7.93946 | 3.115077 |
| 7.9962 | 3.114658 |
| 8.05335 | 3.114232 |
| 8.11091 | 3.113801 |
| 8.16888 | 3.113363 |
| 8.22726 | 3.112918 |
| 8.28607 | 3.112467 |
| 8.34529 | 3.112009 |
| 8.40493 | 3.111544 |
| 8.465 | 3.111072 |
| 8.5255 | 3.110592 |
| 8.58644 | 3.110105 |
| 8.64781 | 3.10961 |
| 8.70961 | 3.109108 |
| 8.77186 | 3.108597 |
| 8.83456 | 3.108078 |
| 8.8977 | 3.107552 |
| 8.96129 | 3.107016 |
| 9.02534 | 3.106472 |
| 9.08985 | 3.10592 |
| 9.15481 | 3.105358 |
| 9.22024 | 3.104787 |
| 9.28614 | 3.104206 |
| 9.35251 | 3.103616 |
| 9.41936 | 3.103016 |
| 9.48668 | 3.102406 |
| 9.55448 | 3.101786 |
| 9.62277 | 3.101156 |
| 9.69155 | 3.100514 |
| 9.76081 | 3.099862 |
| 9.83057 | 3.099199 |
| 9.90084 | 3.098524 |
| 9.9716 | 3.097837 |
| 10.0429 | 3.097139 |
| 10.1146 | 3.096428 |
| 10.1869 | 3.095705 |
| 10.2597 | 3.094969 |
| 10.3331 | 3.094221 |
| 10.4069 | 3.093458 |
| 10.4813 | 3.092682 |
| 10.5562 | 3.091893 |
| 10.6317 | 3.091088 |
| 10.7077 | 3.09027 |
| 10.7842 | 3.089436 |
| 10.8613 | 3.088587 |
| 10.9389 | 3.087722 |
| 11.0171 | 3.086842 |
| 11.0958 | 3.085944 |
| 11.1751 | 3.08503 |
| 11.255 | 3.084099 |
| 11.3354 | 3.083151 |
| 11.4164 | 3.082184 |
| 11.498 | 3.081198 |
| 11.5802 | 3.080194 |
| 11.663 | 3.07917 |
| 11.7463 | 3.078127 |
| 11.8303 | 3.077063 |
| 11.9148 | 3.075978 |
| 12 | 3.074872 |
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.