Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Ghosh 1998: n(o) 0.7–12 µm; 200 K
- Data
- formula 2
- Range
- 0.7–12 µm
- Temperature
- 200 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
- 3.11765
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.71971
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0114 µm⁻¹
- Group index ng
- 3.15071
- Group velocity dispersion
- 378.804 fs²/mm
- Dispersion parameter D
- -84.8436 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; 200 K
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Ghosh-200K-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_5334d20fed43/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-1998-200k-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_5334d20fed43/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 | 3.55320893 |
| C2 | 5.10583525 |
| C3 | 0.13153917 |
| C4 | 2.1689356 |
| C5 | 900.0 |
Comments and conditions
Conditions
- temperature
- 200 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 | 3.395803 |
| 0.705003 | 3.39049 |
| 0.710042 | 3.385299 |
| 0.715117 | 3.380224 |
| 0.720228 | 3.375262 |
| 0.725375 | 3.37041 |
| 0.73056 | 3.365666 |
| 0.735781 | 3.361025 |
| 0.74104 | 3.356486 |
| 0.746336 | 3.352044 |
| 0.75167 | 3.347698 |
| 0.757043 | 3.343445 |
| 0.762453 | 3.339282 |
| 0.767903 | 3.335206 |
| 0.773391 | 3.331217 |
| 0.778919 | 3.32731 |
| 0.784486 | 3.323484 |
| 0.790093 | 3.319737 |
| 0.79574 | 3.316067 |
| 0.801427 | 3.312472 |
| 0.807155 | 3.308949 |
| 0.812924 | 3.305498 |
| 0.818734 | 3.302115 |
| 0.824585 | 3.298801 |
| 0.830479 | 3.295551 |
| 0.836414 | 3.292367 |
| 0.842392 | 3.289244 |
| 0.848413 | 3.286183 |
| 0.854477 | 3.283181 |
| 0.860584 | 3.280238 |
| 0.866735 | 3.277351 |
| 0.87293 | 3.274519 |
| 0.879169 | 3.271742 |
| 0.885452 | 3.269017 |
| 0.891781 | 3.266344 |
| 0.898154 | 3.263721 |
| 0.904574 | 3.261148 |
| 0.911039 | 3.258623 |
| 0.91755 | 3.256144 |
| 0.924108 | 3.253712 |
| 0.930713 | 3.251324 |
| 0.937365 | 3.24898 |
| 0.944064 | 3.24668 |
| 0.950812 | 3.244421 |
| 0.957607 | 3.242203 |
| 0.964451 | 3.240025 |
| 0.971345 | 3.237887 |
| 0.978287 | 3.235787 |
| 0.985279 | 3.233725 |
| 0.992321 | 3.231699 |
| 0.999413 | 3.229709 |
| 1.00656 | 3.227755 |
| 1.01375 | 3.225835 |
| 1.021 | 3.223949 |
| 1.02829 | 3.222096 |
| 1.03564 | 3.220275 |
| 1.04304 | 3.218486 |
| 1.0505 | 3.216728 |
| 1.05801 | 3.215 |
| 1.06557 | 3.213303 |
| 1.07318 | 3.211634 |
| 1.08085 | 3.209994 |
| 1.08858 | 3.208382 |
| 1.09636 | 3.206797 |
| 1.1042 | 3.20524 |
| 1.11209 | 3.203708 |
| 1.12004 | 3.202203 |
| 1.12804 | 3.200723 |
| 1.1361 | 3.199268 |
| 1.14422 | 3.197837 |
| 1.1524 | 3.19643 |
| 1.16064 | 3.195046 |
| 1.16893 | 3.193685 |
| 1.17729 | 3.192347 |
| 1.1857 | 3.191031 |
| 1.19418 | 3.189736 |
| 1.20271 | 3.188463 |
| 1.21131 | 3.187211 |
| 1.21997 | 3.185979 |
| 1.22868 | 3.184767 |
| 1.23747 | 3.183575 |
| 1.24631 | 3.182402 |
| 1.25522 | 3.181248 |
| 1.26419 | 3.180113 |
| 1.27322 | 3.178996 |
| 1.28232 | 3.177896 |
| 1.29149 | 3.176815 |
| 1.30072 | 3.17575 |
| 1.31002 | 3.174703 |
| 1.31938 | 3.173672 |
| 1.32881 | 3.172658 |
| 1.33831 | 3.171659 |
| 1.34787 | 3.170677 |
| 1.35751 | 3.16971 |
| 1.36721 | 3.168757 |
| 1.37698 | 3.16782 |
| 1.38682 | 3.166898 |
| 1.39673 | 3.16599 |
| 1.40672 | 3.165096 |
| 1.41677 | 3.164215 |
| 1.4269 | 3.163349 |
| 1.43709 | 3.162496 |
| 1.44736 | 3.161655 |
| 1.45771 | 3.160828 |
| 1.46813 | 3.160014 |
| 1.47862 | 3.159212 |
| 1.48919 | 3.158422 |
| 1.49983 | 3.157644 |
| 1.51055 | 3.156878 |
| 1.52135 | 3.156124 |
| 1.53222 | 3.15538 |
| 1.54317 | 3.154649 |
| 1.5542 | 3.153928 |
| 1.56531 | 3.153218 |
| 1.5765 | 3.152518 |
| 1.58776 | 3.151829 |
| 1.59911 | 3.15115 |
| 1.61054 | 3.150482 |
| 1.62205 | 3.149823 |
| 1.63365 | 3.149174 |
| 1.64532 | 3.148534 |
| 1.65708 | 3.147904 |
| 1.66892 | 3.147283 |
| 1.68085 | 3.146671 |
| 1.69287 | 3.146068 |
| 1.70497 | 3.145474 |
| 1.71715 | 3.144889 |
| 1.72942 | 3.144312 |
| 1.74178 | 3.143743 |
| 1.75423 | 3.143182 |
| 1.76677 | 3.14263 |
| 1.7794 | 3.142085 |
| 1.79212 | 3.141548 |
| 1.80492 | 3.141019 |
| 1.81782 | 3.140497 |
| 1.83082 | 3.139983 |
| 1.8439 | 3.139475 |
| 1.85708 | 3.138975 |
| 1.87035 | 3.138482 |
| 1.88372 | 3.137996 |
| 1.89719 | 3.137516 |
| 1.91074 | 3.137044 |
| 1.9244 | 3.136577 |
| 1.93816 | 3.136117 |
| 1.95201 | 3.135664 |
| 1.96596 | 3.135216 |
| 1.98001 | 3.134775 |
| 1.99416 | 3.13434 |
| 2.00841 | 3.13391 |
| 2.02277 | 3.133486 |
| 2.03723 | 3.133068 |
| 2.05179 | 3.132656 |
| 2.06645 | 3.132249 |
| 2.08122 | 3.131847 |
| 2.09609 | 3.131451 |
| 2.11108 | 3.13106 |
| 2.12616 | 3.130674 |
| 2.14136 | 3.130292 |
| 2.15666 | 3.129916 |
| 2.17208 | 3.129545 |
| 2.1876 | 3.129178 |
| 2.20324 | 3.128816 |
| 2.21899 | 3.128459 |
| 2.23484 | 3.128106 |
| 2.25082 | 3.127758 |
| 2.2669 | 3.127414 |
| 2.28311 | 3.127074 |
| 2.29942 | 3.126738 |
| 2.31586 | 3.126406 |
| 2.33241 | 3.126079 |
| 2.34908 | 3.125755 |
| 2.36587 | 3.125435 |
| 2.38278 | 3.12512 |
| 2.39981 | 3.124807 |
| 2.41696 | 3.124499 |
| 2.43424 | 3.124194 |
| 2.45163 | 3.123892 |
| 2.46916 | 3.123594 |
| 2.4868 | 3.1233 |
| 2.50458 | 3.123008 |
| 2.52248 | 3.12272 |
| 2.54051 | 3.122435 |
| 2.55866 | 3.122154 |
| 2.57695 | 3.121875 |
| 2.59537 | 3.121599 |
| 2.61392 | 3.121326 |
| 2.6326 | 3.121056 |
| 2.65142 | 3.120789 |
| 2.67037 | 3.120525 |
| 2.68945 | 3.120263 |
| 2.70867 | 3.120004 |
| 2.72803 | 3.119748 |
| 2.74753 | 3.119494 |
| 2.76717 | 3.119243 |
| 2.78695 | 3.118994 |
| 2.80686 | 3.118747 |
| 2.82693 | 3.118503 |
| 2.84713 | 3.118261 |
| 2.86748 | 3.118021 |
| 2.88797 | 3.117783 |
| 2.90861 | 3.117548 |
| 2.9294 | 3.117314 |
| 2.95034 | 3.117083 |
| 2.97143 | 3.116853 |
| 2.99266 | 3.116625 |
| 3.01405 | 3.116399 |
| 3.03559 | 3.116175 |
| 3.05729 | 3.115953 |
| 3.07914 | 3.115732 |
| 3.10115 | 3.115513 |
| 3.12331 | 3.115296 |
| 3.14564 | 3.11508 |
| 3.16812 | 3.114865 |
| 3.19076 | 3.114652 |
| 3.21357 | 3.114441 |
| 3.23653 | 3.114231 |
| 3.25967 | 3.114022 |
| 3.28296 | 3.113814 |
| 3.30643 | 3.113608 |
| 3.33006 | 3.113403 |
| 3.35386 | 3.113199 |
| 3.37783 | 3.112996 |
| 3.40197 | 3.112794 |
| 3.42629 | 3.112593 |
| 3.45078 | 3.112394 |
| 3.47544 | 3.112195 |
| 3.50028 | 3.111997 |
| 3.5253 | 3.111799 |
| 3.55049 | 3.111603 |
| 3.57587 | 3.111407 |
| 3.60142 | 3.111212 |
| 3.62716 | 3.111018 |
| 3.65309 | 3.110824 |
| 3.6792 | 3.110631 |
| 3.70549 | 3.110439 |
| 3.73198 | 3.110247 |
| 3.75865 | 3.110055 |
| 3.78551 | 3.109864 |
| 3.81257 | 3.109673 |
| 3.83982 | 3.109482 |
| 3.86726 | 3.109292 |
| 3.8949 | 3.109102 |
| 3.92274 | 3.108913 |
| 3.95078 | 3.108723 |
| 3.97901 | 3.108534 |
| 4.00745 | 3.108344 |
| 4.03609 | 3.108155 |
| 4.06494 | 3.107966 |
| 4.09399 | 3.107776 |
| 4.12325 | 3.107587 |
| 4.15272 | 3.107397 |
| 4.1824 | 3.107207 |
| 4.2123 | 3.107018 |
| 4.2424 | 3.106827 |
| 4.27272 | 3.106637 |
| 4.30326 | 3.106446 |
| 4.33402 | 3.106255 |
| 4.36499 | 3.106063 |
| 4.39619 | 3.105871 |
| 4.42761 | 3.105679 |
| 4.45926 | 3.105485 |
| 4.49113 | 3.105292 |
| 4.52323 | 3.105097 |
| 4.55556 | 3.104902 |
| 4.58812 | 3.104707 |
| 4.62091 | 3.10451 |
| 4.65393 | 3.104313 |
| 4.6872 | 3.104115 |
| 4.7207 | 3.103916 |
| 4.75444 | 3.103716 |
| 4.78842 | 3.103515 |
| 4.82264 | 3.103313 |
| 4.85711 | 3.103109 |
| 4.89182 | 3.102905 |
| 4.92679 | 3.1027 |
| 4.962 | 3.102493 |
| 4.99746 | 3.102285 |
| 5.03318 | 3.102076 |
| 5.06915 | 3.101865 |
| 5.10538 | 3.101653 |
| 5.14187 | 3.10144 |
| 5.17862 | 3.101225 |
| 5.21564 | 3.101008 |
| 5.25291 | 3.10079 |
| 5.29046 | 3.10057 |
| 5.32827 | 3.100349 |
| 5.36635 | 3.100126 |
| 5.4047 | 3.0999 |
| 5.44333 | 3.099673 |
| 5.48224 | 3.099445 |
| 5.52142 | 3.099214 |
| 5.56088 | 3.098981 |
| 5.60063 | 3.098746 |
| 5.64066 | 3.098508 |
| 5.68097 | 3.098269 |
| 5.72157 | 3.098027 |
| 5.76247 | 3.097783 |
| 5.80365 | 3.097537 |
| 5.84513 | 3.097288 |
| 5.88691 | 3.097037 |
| 5.92898 | 3.096783 |
| 5.97136 | 3.096526 |
| 6.01404 | 3.096267 |
| 6.05702 | 3.096005 |
| 6.10031 | 3.09574 |
| 6.14391 | 3.095472 |
| 6.18782 | 3.095201 |
| 6.23205 | 3.094928 |
| 6.27659 | 3.094651 |
| 6.32145 | 3.094371 |
| 6.36663 | 3.094087 |
| 6.41213 | 3.093801 |
| 6.45796 | 3.093511 |
| 6.50412 | 3.093217 |
| 6.5506 | 3.09292 |
| 6.59742 | 3.09262 |
| 6.64457 | 3.092315 |
| 6.69206 | 3.092007 |
| 6.73989 | 3.091695 |
| 6.78807 | 3.091379 |
| 6.83658 | 3.091059 |
| 6.88544 | 3.090735 |
| 6.93465 | 3.090407 |
| 6.98422 | 3.090074 |
| 7.03414 | 3.089737 |
| 7.08441 | 3.089396 |
| 7.13504 | 3.08905 |
| 7.18604 | 3.088699 |
| 7.2374 | 3.088344 |
| 7.28913 | 3.087983 |
| 7.34122 | 3.087618 |
| 7.39369 | 3.087247 |
| 7.44654 | 3.086872 |
| 7.49976 | 3.086491 |
| 7.55336 | 3.086105 |
| 7.60734 | 3.085713 |
| 7.66172 | 3.085316 |
| 7.71647 | 3.084913 |
| 7.77163 | 3.084504 |
| 7.82717 | 3.084089 |
| 7.88311 | 3.083668 |
| 7.93946 | 3.08324 |
| 7.9962 | 3.082807 |
| 8.05335 | 3.082366 |
| 8.11091 | 3.08192 |
| 8.16888 | 3.081466 |
| 8.22726 | 3.081006 |
| 8.28607 | 3.080538 |
| 8.34529 | 3.080064 |
| 8.40493 | 3.079582 |
| 8.465 | 3.079092 |
| 8.5255 | 3.078595 |
| 8.58644 | 3.07809 |
| 8.64781 | 3.077577 |
| 8.70961 | 3.077056 |
| 8.77186 | 3.076527 |
| 8.83456 | 3.075989 |
| 8.8977 | 3.075443 |
| 8.96129 | 3.074887 |
| 9.02534 | 3.074323 |
| 9.08985 | 3.07375 |
| 9.15481 | 3.073167 |
| 9.22024 | 3.072574 |
| 9.28614 | 3.071972 |
| 9.35251 | 3.071359 |
| 9.41936 | 3.070736 |
| 9.48668 | 3.070103 |
| 9.55448 | 3.069459 |
| 9.62277 | 3.068805 |
| 9.69155 | 3.068139 |
| 9.76081 | 3.067461 |
| 9.83057 | 3.066772 |
| 9.90084 | 3.066071 |
| 9.9716 | 3.065358 |
| 10.0429 | 3.064632 |
| 10.1146 | 3.063894 |
| 10.1869 | 3.063143 |
| 10.2597 | 3.062378 |
| 10.3331 | 3.0616 |
| 10.4069 | 3.060807 |
| 10.4813 | 3.060001 |
| 10.5562 | 3.05918 |
| 10.6317 | 3.058344 |
| 10.7077 | 3.057493 |
| 10.7842 | 3.056626 |
| 10.8613 | 3.055743 |
| 10.9389 | 3.054844 |
| 11.0171 | 3.053929 |
| 11.0958 | 3.052996 |
| 11.1751 | 3.052045 |
| 11.255 | 3.051077 |
| 11.3354 | 3.05009 |
| 11.4164 | 3.049084 |
| 11.498 | 3.048059 |
| 11.5802 | 3.047015 |
| 11.663 | 3.04595 |
| 11.7463 | 3.044864 |
| 11.8303 | 3.043757 |
| 11.9148 | 3.042628 |
| 12 | 3.041477 |
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.