Optical constants
Refractive index of ZnGeP2 (Zinc germanium phosphide, ZGP)
Boyd et al. 1971: n(o) 0.64–12 µm; 20 °C
- Data
- formula 2
- Range
- 0.64–12 µm
- Temperature
- 293 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
- 3.1329
- Extinction coefficient k
- 0
- Permittivity ε1
- 9.81509
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- -0.0129966 µm⁻¹
- Group index ng
- 3.1689
- Group velocity dispersion
- 426.335 fs²/mm
- Dispersion parameter D
- -104.663 ps/(nm·km)
- Photon energy
- 0.447596 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): Boyd et al. 1971: n(o) 0.64–12 µm; 20 °C
zngep2 = ls.fetch_refractiveindex("main", "ZnGeP2", "Boyd-20C-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(zngep2.range_nm) # (640, 12000) nm
eps = zngep2.eps([2770]) # 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_d7031e90850c/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/boyd-1971-20c-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=640, 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_d7031e90850c/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 0.64 to 12.0 µm.
Coefficients as stored
| Ci | Value |
|---|---|
| C1 | 3.4733 |
| C2 | 5.2658 |
| C3 | 0.1338 |
| C4 | 1.4909 |
| C5 | 662.55 |
Comments and conditions
Conditions
- temperature
- 293 K
- direction
- o
References
1) G. D. Boyd, E. Buehler, F. G Storz.
Linear and nonlinear optical properties of ZnGeP2 and CdSe.
Appl. Phys. Lett., 18, 301-304 (1971)
2) G. C. Bhar and G. Ghosh. Temperature-dependent Sellmeier coefficients and coherence lengths for some chalcopyrite crystals. J. Opt. Soc. Am. 69, 730-733 (1979)
* Ref. 2 provides a dispersion formula based on data from Ref. 1
2) G. C. Bhar and G. Ghosh. Temperature-dependent Sellmeier coefficients and coherence lengths for some chalcopyrite crystals. J. Opt. Soc. Am. 69, 730-733 (1979)
* Ref. 2 provides a dispersion formula based on data from Ref. 1
- doi:10.1063/1.1653673 LINEAR AND NONLINEAR OPTICAL PROPERTIES OF ZnGeP2 AND CdSe, Applied Physics Letters (1971)
- doi:10.1364/josa.69.000730 Temperature-dependent Sellmeier coefficients and coherence lengths for some chalcopyrite crystals, Journal of the Optical Society of America (1979)
Cite
G. D. Boyd, E. Buehler and F. G. Storz. LINEAR AND NONLINEAR OPTICAL PROPERTIES OF ZnGeP2 AND CdSe. Applied Physics Letters, 18, 301-304 (1971), doi:10.1063/1.1653673; Gopal C. Bhar and Gorachand Ghosh. Temperature-dependent Sellmeier coefficients and coherence lengths for some chalcopyrite crystals. Journal of the Optical Society of America, 69, 730 (1979), doi:10.1364/josa.69.000730; 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 |
|---|---|
| 0.64 | 3.506109 |
| 0.644719 | 3.498262 |
| 0.649473 | 3.49062 |
| 0.654262 | 3.483175 |
| 0.659086 | 3.475921 |
| 0.663945 | 3.468851 |
| 0.668841 | 3.461959 |
| 0.673773 | 3.455239 |
| 0.678741 | 3.448685 |
| 0.683745 | 3.442291 |
| 0.688787 | 3.436053 |
| 0.693865 | 3.429966 |
| 0.698982 | 3.424025 |
| 0.704135 | 3.418224 |
| 0.709327 | 3.412561 |
| 0.714557 | 3.40703 |
| 0.719826 | 3.401627 |
| 0.725134 | 3.396349 |
| 0.73048 | 3.391192 |
| 0.735867 | 3.386152 |
| 0.741292 | 3.381226 |
| 0.746758 | 3.376411 |
| 0.752264 | 3.371702 |
| 0.757811 | 3.367098 |
| 0.763399 | 3.362596 |
| 0.769028 | 3.358192 |
| 0.774698 | 3.353883 |
| 0.78041 | 3.349667 |
| 0.786164 | 3.345542 |
| 0.791961 | 3.341505 |
| 0.797801 | 3.337554 |
| 0.803683 | 3.333686 |
| 0.809609 | 3.329899 |
| 0.815579 | 3.326191 |
| 0.821592 | 3.32256 |
| 0.82765 | 3.319003 |
| 0.833753 | 3.31552 |
| 0.8399 | 3.312108 |
| 0.846093 | 3.308765 |
| 0.852332 | 3.30549 |
| 0.858616 | 3.30228 |
| 0.864947 | 3.299135 |
| 0.871325 | 3.296052 |
| 0.877749 | 3.29303 |
| 0.884221 | 3.290068 |
| 0.890741 | 3.287164 |
| 0.897309 | 3.284317 |
| 0.903925 | 3.281525 |
| 0.91059 | 3.278787 |
| 0.917304 | 3.276102 |
| 0.924068 | 3.273469 |
| 0.930882 | 3.270886 |
| 0.937745 | 3.268352 |
| 0.94466 | 3.265866 |
| 0.951625 | 3.263427 |
| 0.958642 | 3.261034 |
| 0.96571 | 3.258685 |
| 0.972831 | 3.256381 |
| 0.980004 | 3.254119 |
| 0.98723 | 3.251899 |
| 0.994509 | 3.249721 |
| 1.00184 | 3.247582 |
| 1.00923 | 3.245482 |
| 1.01667 | 3.243421 |
| 1.02417 | 3.241397 |
| 1.03172 | 3.239409 |
| 1.03933 | 3.237458 |
| 1.04699 | 3.235542 |
| 1.05471 | 3.23366 |
| 1.06249 | 3.231812 |
| 1.07032 | 3.229996 |
| 1.07821 | 3.228213 |
| 1.08616 | 3.226462 |
| 1.09417 | 3.224741 |
| 1.10224 | 3.22305 |
| 1.11037 | 3.22139 |
| 1.11855 | 3.219758 |
| 1.1268 | 3.218155 |
| 1.13511 | 3.216579 |
| 1.14348 | 3.215031 |
| 1.15191 | 3.213509 |
| 1.1604 | 3.212014 |
| 1.16896 | 3.210545 |
| 1.17758 | 3.2091 |
| 1.18626 | 3.20768 |
| 1.19501 | 3.206285 |
| 1.20382 | 3.204913 |
| 1.2127 | 3.203564 |
| 1.22164 | 3.202238 |
| 1.23064 | 3.200935 |
| 1.23972 | 3.199653 |
| 1.24886 | 3.198393 |
| 1.25807 | 3.197154 |
| 1.26734 | 3.195935 |
| 1.27669 | 3.194737 |
| 1.2861 | 3.193559 |
| 1.29559 | 3.1924 |
| 1.30514 | 3.19126 |
| 1.31476 | 3.190139 |
| 1.32446 | 3.189037 |
| 1.33422 | 3.187952 |
| 1.34406 | 3.186885 |
| 1.35397 | 3.185836 |
| 1.36395 | 3.184804 |
| 1.37401 | 3.183788 |
| 1.38414 | 3.182789 |
| 1.39435 | 3.181806 |
| 1.40463 | 3.180838 |
| 1.41498 | 3.179887 |
| 1.42542 | 3.17895 |
| 1.43593 | 3.178029 |
| 1.44652 | 3.177122 |
| 1.45718 | 3.17623 |
| 1.46793 | 3.175351 |
| 1.47875 | 3.174487 |
| 1.48965 | 3.173636 |
| 1.50064 | 3.172799 |
| 1.5117 | 3.171975 |
| 1.52285 | 3.171164 |
| 1.53408 | 3.170365 |
| 1.54539 | 3.169579 |
| 1.55678 | 3.168805 |
| 1.56826 | 3.168043 |
| 1.57982 | 3.167293 |
| 1.59147 | 3.166555 |
| 1.60321 | 3.165828 |
| 1.61503 | 3.165112 |
| 1.62694 | 3.164407 |
| 1.63893 | 3.163713 |
| 1.65102 | 3.16303 |
| 1.66319 | 3.162357 |
| 1.67546 | 3.161694 |
| 1.68781 | 3.161041 |
| 1.70025 | 3.160398 |
| 1.71279 | 3.159765 |
| 1.72542 | 3.159141 |
| 1.73814 | 3.158526 |
| 1.75096 | 3.157921 |
| 1.76387 | 3.157325 |
| 1.77687 | 3.156738 |
| 1.78998 | 3.156159 |
| 1.80317 | 3.155589 |
| 1.81647 | 3.155027 |
| 1.82986 | 3.154474 |
| 1.84336 | 3.153928 |
| 1.85695 | 3.153391 |
| 1.87064 | 3.152861 |
| 1.88443 | 3.152339 |
| 1.89833 | 3.151825 |
| 1.91232 | 3.151318 |
| 1.92642 | 3.150818 |
| 1.94063 | 3.150326 |
| 1.95494 | 3.14984 |
| 1.96935 | 3.149362 |
| 1.98387 | 3.14889 |
| 1.9985 | 3.148425 |
| 2.01324 | 3.147966 |
| 2.02808 | 3.147514 |
| 2.04303 | 3.147068 |
| 2.0581 | 3.146628 |
| 2.07327 | 3.146195 |
| 2.08856 | 3.145767 |
| 2.10396 | 3.145345 |
| 2.11947 | 3.144929 |
| 2.1351 | 3.144519 |
| 2.15084 | 3.144114 |
| 2.1667 | 3.143715 |
| 2.18268 | 3.143321 |
| 2.19877 | 3.142932 |
| 2.21499 | 3.142549 |
| 2.23132 | 3.14217 |
| 2.24777 | 3.141797 |
| 2.26434 | 3.141428 |
| 2.28104 | 3.141064 |
| 2.29786 | 3.140705 |
| 2.3148 | 3.140351 |
| 2.33187 | 3.140001 |
| 2.34906 | 3.139655 |
| 2.36638 | 3.139314 |
| 2.38383 | 3.138977 |
| 2.40141 | 3.138644 |
| 2.41912 | 3.138316 |
| 2.43695 | 3.137991 |
| 2.45492 | 3.137671 |
| 2.47302 | 3.137354 |
| 2.49126 | 3.137041 |
| 2.50963 | 3.136732 |
| 2.52813 | 3.136426 |
| 2.54677 | 3.136124 |
| 2.56555 | 3.135826 |
| 2.58447 | 3.135531 |
| 2.60352 | 3.135239 |
| 2.62272 | 3.134951 |
| 2.64206 | 3.134666 |
| 2.66154 | 3.134384 |
| 2.68116 | 3.134105 |
| 2.70093 | 3.133829 |
| 2.72085 | 3.133557 |
| 2.74091 | 3.133287 |
| 2.76112 | 3.13302 |
| 2.78148 | 3.132755 |
| 2.80199 | 3.132494 |
| 2.82265 | 3.132235 |
| 2.84346 | 3.131979 |
| 2.86443 | 3.131725 |
| 2.88555 | 3.131473 |
| 2.90682 | 3.131224 |
| 2.92826 | 3.130978 |
| 2.94985 | 3.130734 |
| 2.9716 | 3.130492 |
| 2.99351 | 3.130252 |
| 3.01558 | 3.130014 |
| 3.03782 | 3.129778 |
| 3.06022 | 3.129545 |
| 3.08278 | 3.129313 |
| 3.10551 | 3.129083 |
| 3.12841 | 3.128855 |
| 3.15148 | 3.128629 |
| 3.17471 | 3.128405 |
| 3.19812 | 3.128182 |
| 3.2217 | 3.127961 |
| 3.24546 | 3.127742 |
| 3.26939 | 3.127524 |
| 3.29349 | 3.127307 |
| 3.31778 | 3.127092 |
| 3.34224 | 3.126879 |
| 3.36689 | 3.126666 |
| 3.39171 | 3.126455 |
| 3.41672 | 3.126246 |
| 3.44191 | 3.126037 |
| 3.46729 | 3.12583 |
| 3.49286 | 3.125624 |
| 3.51861 | 3.125418 |
| 3.54455 | 3.125214 |
| 3.57069 | 3.125011 |
| 3.59702 | 3.124809 |
| 3.62354 | 3.124607 |
| 3.65026 | 3.124406 |
| 3.67717 | 3.124207 |
| 3.70429 | 3.124007 |
| 3.7316 | 3.123809 |
| 3.75911 | 3.123611 |
| 3.78683 | 3.123414 |
| 3.81475 | 3.123217 |
| 3.84288 | 3.123021 |
| 3.87122 | 3.122825 |
| 3.89976 | 3.122629 |
| 3.92851 | 3.122434 |
| 3.95748 | 3.122239 |
| 3.98666 | 3.122045 |
| 4.01606 | 3.12185 |
| 4.04567 | 3.121656 |
| 4.0755 | 3.121462 |
| 4.10555 | 3.121268 |
| 4.13582 | 3.121074 |
| 4.16632 | 3.12088 |
| 4.19704 | 3.120686 |
| 4.22798 | 3.120492 |
| 4.25916 | 3.120298 |
| 4.29056 | 3.120103 |
| 4.3222 | 3.119909 |
| 4.35407 | 3.119713 |
| 4.38617 | 3.119518 |
| 4.41851 | 3.119322 |
| 4.45109 | 3.119126 |
| 4.48391 | 3.118929 |
| 4.51697 | 3.118732 |
| 4.55028 | 3.118534 |
| 4.58383 | 3.118336 |
| 4.61763 | 3.118137 |
| 4.65168 | 3.117937 |
| 4.68597 | 3.117736 |
| 4.72053 | 3.117534 |
| 4.75533 | 3.117332 |
| 4.79039 | 3.117129 |
| 4.82572 | 3.116924 |
| 4.8613 | 3.116719 |
| 4.89714 | 3.116513 |
| 4.93325 | 3.116305 |
| 4.96963 | 3.116096 |
| 5.00627 | 3.115886 |
| 5.04318 | 3.115675 |
| 5.08037 | 3.115463 |
| 5.11783 | 3.115249 |
| 5.15556 | 3.115033 |
| 5.19358 | 3.114816 |
| 5.23187 | 3.114597 |
| 5.27045 | 3.114377 |
| 5.30931 | 3.114155 |
| 5.34846 | 3.113932 |
| 5.38789 | 3.113706 |
| 5.42762 | 3.113479 |
| 5.46764 | 3.11325 |
| 5.50796 | 3.113018 |
| 5.54857 | 3.112785 |
| 5.58948 | 3.11255 |
| 5.63069 | 3.112312 |
| 5.67221 | 3.112073 |
| 5.71403 | 3.11183 |
| 5.75617 | 3.111586 |
| 5.79861 | 3.111339 |
| 5.84136 | 3.11109 |
| 5.88443 | 3.110838 |
| 5.92782 | 3.110583 |
| 5.97153 | 3.110326 |
| 6.01556 | 3.110066 |
| 6.05992 | 3.109803 |
| 6.1046 | 3.109537 |
| 6.14961 | 3.109268 |
| 6.19495 | 3.108996 |
| 6.24063 | 3.108721 |
| 6.28665 | 3.108442 |
| 6.333 | 3.10816 |
| 6.3797 | 3.107875 |
| 6.42674 | 3.107586 |
| 6.47412 | 3.107294 |
| 6.52186 | 3.106998 |
| 6.56995 | 3.106698 |
| 6.61839 | 3.106395 |
| 6.66719 | 3.106087 |
| 6.71635 | 3.105776 |
| 6.76587 | 3.10546 |
| 6.81576 | 3.10514 |
| 6.86602 | 3.104816 |
| 6.91664 | 3.104487 |
| 6.96764 | 3.104154 |
| 7.01902 | 3.103816 |
| 7.07077 | 3.103473 |
| 7.12291 | 3.103126 |
| 7.17543 | 3.102773 |
| 7.22833 | 3.102415 |
| 7.28163 | 3.102053 |
| 7.33532 | 3.101684 |
| 7.38941 | 3.101311 |
| 7.44389 | 3.100932 |
| 7.49878 | 3.100547 |
| 7.55407 | 3.100156 |
| 7.60977 | 3.099759 |
| 7.66588 | 3.099356 |
| 7.7224 | 3.098947 |
| 7.77934 | 3.098532 |
| 7.8367 | 3.098109 |
| 7.89449 | 3.097681 |
| 7.9527 | 3.097245 |
| 8.01133 | 3.096802 |
| 8.07041 | 3.096353 |
| 8.12991 | 3.095895 |
| 8.18986 | 3.095431 |
| 8.25024 | 3.094958 |
| 8.31108 | 3.094478 |
| 8.37236 | 3.09399 |
| 8.43409 | 3.093494 |
| 8.49628 | 3.092989 |
| 8.55892 | 3.092475 |
| 8.62203 | 3.091953 |
| 8.68561 | 3.091421 |
| 8.74965 | 3.090881 |
| 8.81416 | 3.09033 |
| 8.87915 | 3.089771 |
| 8.94462 | 3.089201 |
| 9.01058 | 3.088621 |
| 9.07701 | 3.08803 |
| 9.14394 | 3.087429 |
| 9.21136 | 3.086818 |
| 9.27928 | 3.086194 |
| 9.3477 | 3.08556 |
| 9.41663 | 3.084913 |
| 9.48606 | 3.084255 |
| 9.55601 | 3.083584 |
| 9.62647 | 3.082901 |
| 9.69745 | 3.082204 |
| 9.76895 | 3.081495 |
| 9.84098 | 3.080772 |
| 9.91354 | 3.080034 |
| 9.98664 | 3.079283 |
| 10.0603 | 3.078516 |
| 10.1345 | 3.077735 |
| 10.2092 | 3.076938 |
| 10.2845 | 3.076125 |
| 10.3603 | 3.075296 |
| 10.4367 | 3.074451 |
| 10.5136 | 3.073588 |
| 10.5911 | 3.072707 |
| 10.6692 | 3.071808 |
| 10.7479 | 3.070891 |
| 10.8272 | 3.069954 |
| 10.907 | 3.068998 |
| 10.9874 | 3.068022 |
| 11.0684 | 3.067025 |
| 11.15 | 3.066006 |
| 11.2323 | 3.064966 |
| 11.3151 | 3.063903 |
| 11.3985 | 3.062817 |
| 11.4826 | 3.061706 |
| 11.5672 | 3.060571 |
| 11.6525 | 3.059411 |
| 11.7384 | 3.058225 |
| 11.825 | 3.057012 |
| 11.9122 | 3.055771 |
| 12 | 3.054501 |
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
- —
Ordinary ray (o); 20 °C