Optical constants

Refractive index of CdGeP2 (Cadmium germanium phosphide)

Boyd et al. 1972: n(e) 0.8–12.5 µm; 20 °C

Data
formula 2
Range
0.8–12.5 µm
Optical axis
e
Licence
CC0-1.0

Uniaxial crystal, axes: oe

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.8–12.5 µm
Refractive index n
3.21398
Extinction coefficient k
0
Permittivity ε1
10.3296
Permittivity ε2
0
Absorption coefficient α
0 cm⁻¹
Penetration depth δ = λ/(2πk)
— nm
Abbe number Vd
—
Chromatic dispersion dn/dλ
-0.0121203 µm⁻¹
Group index ng
3.25228
Group velocity dispersion
495.367 fs²/mm
Dispersion parameter D
-93.4444 ps/(nm·km)
Photon energy
0.392355 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

# CdGeP2 (Cadmium germanium phosphide): Boyd et al. 1972: n(e) 0.8–12.5 µm; 20 °C
cdgep2 = ls.fetch_refractiveindex("main", "CdGeP2", "Boyd-20-e", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cdgep2.range_nm)  # (800, 12500) nm
eps = cdgep2.eps([3160])  # complex permittivity

Downloads the original record once (pinned to the imported snapshot) and caches it.

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 µm
n2−1=5.1573+4.097λ2λ2−0.233+1.4925λ2λ2−671.33

Valid from 0.8 to 12.5 µm.

Coefficients as stored
CiValue
C15.1573
C24.097
C30.233
C41.4925
C5671.33

Comments and conditions

Extrardinary ray (e); 20 °C

References

1) G. D. Boyd, E. Buehler, F. G Storz, J. H. Wernick. Linear and nonlinear optical properties of ternary AIIBIVC2V chalcopyrite semiconductors. IEEE J. Quantum Electron., 8, 419-426 (1972)
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:10.1109/jqe.1972.1076982 Linear and nonlinear optical properties of ternary A<sup>II</sup>B<sup>IV</sup>C<inf>2</inf><sup>V</sup>chalcopyrite semiconductors, IEEE Journal of Quantum Electronics (1972)
  • 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. Boyd, E. Buehler, F. Storz and J. Wernick. Linear and nonlinear optical properties of ternary A<sup>II</sup>B<sup>IV</sup>C<inf>2</inf><sup>V</sup>chalcopyrite semiconductors. IEEE Journal of Quantum Electronics, 8, 419-426 (1972), doi:10.1109/jqe.1972.1076982; 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
CdGeP2 (Cadmium germanium phosphide), Boyd et al. 1972: n(e) 0.8–12.5 µm; 20 °C: n and k versus wavelength
λ (µm)n
0.83.549413
0.8055313.542349
0.8110993.535474
0.8167073.528783
0.8223533.522267
0.8280383.515922
0.8337623.50974
0.8395263.503717
0.845333.497846
0.8511743.492123
0.8570583.486542
0.8629833.481098
0.8689493.475788
0.8749563.470607
0.8810053.46555
0.8870963.460613
0.8932283.455794
0.8994033.451087
0.9056213.446491
0.9118823.442
0.9181863.437612
0.9245333.433324
0.9309253.429133
0.9373613.425035
0.9438413.421029
0.9503663.417112
0.9569363.41328
0.9635513.409532
0.9702123.405865
0.976923.402277
0.9836733.398765
0.9904743.395328
0.9973213.391964
1.004223.38867
1.011163.385445
1.018153.382286
1.025193.379192
1.032273.376162
1.039413.373193
1.04663.370285
1.053833.367435
1.061123.364641
1.068453.361904
1.075843.35922
1.083283.356589
1.090773.35401
1.098313.351481
1.10593.349001
1.113543.346569
1.121243.344183
1.128993.341843
1.13683.339547
1.144663.337295
1.152573.335085
1.160543.332916
1.168563.330788
1.176643.328699
1.184773.326648
1.192973.324636
1.201213.32266
1.209523.32072
1.217883.318816
1.22633.316945
1.234783.315109
1.243313.313305
1.251913.311534
1.260563.309794
1.269283.308084
1.278053.306405
1.286893.304756
1.295783.303135
1.304743.301542
1.313763.299978
1.322843.29844
1.331993.296928
1.34123.295443
1.350473.293983
1.35983.292548
1.36923.291137
1.378673.28975
1.38823.288387
1.39783.287046
1.407463.285728
1.417193.284432
1.426993.283158
1.436853.281904
1.446793.280671
1.456793.279459
1.466863.278267
1.4773.277094
1.487213.27594
1.497493.274805
1.507853.273688
1.518273.272589
1.528773.271508
1.539333.270445
1.549983.269398
1.560693.268368
1.571483.267355
1.582343.266357
1.593283.265376
1.60433.26441
1.615393.263459
1.626563.262523
1.63783.261601
1.649123.260694
1.660523.259801
1.6723.258922
1.683563.258056
1.69523.257204
1.706923.256365
1.718723.255538
1.73063.254725
1.742573.253923
1.754613.253134
1.766743.252357
1.778963.251591
1.791263.250837
1.803643.250094
1.816113.249363
1.828663.248642
1.84133.247932
1.854033.247232
1.866853.246543
1.879763.245864
1.892753.245195
1.905843.244536
1.919013.243886
1.932283.243245
1.945643.242614
1.959093.241993
1.972633.24138
1.986273.240775
23.24018
2.013833.239593
2.027753.239014
2.041773.238444
2.055883.237881
2.070093.237326
2.084413.23678
2.098823.23624
2.113323.235709
2.127933.235184
2.142653.234667
2.157463.234157
2.172373.233654
2.187393.233158
2.202513.232669
2.217743.232186
2.233073.23171
2.248513.23124
2.264053.230776
2.27973.230319
2.295463.229867
2.311333.229422
2.327313.228982
2.34343.228548
2.35963.22812
2.375913.227697
2.392343.22728
2.408883.226868
2.425533.226462
2.44233.22606
2.459183.225664
2.476183.225272
2.49333.224886
2.510543.224504
2.527893.224127
2.545373.223754
2.562973.223386
2.580693.223023
2.598533.222664
2.616493.222309
2.634583.221958
2.652793.221612
2.671133.221269
2.68963.220931
2.708193.220596
2.726913.220266
2.745773.219939
2.764753.219615
2.783863.219296
2.803113.218979
2.822483.218667
2.8423.218357
2.861643.218051
2.881433.217749
2.901353.217449
2.92143.217153
2.94163.216859
2.961943.216569
2.982413.216282
3.003033.215997
3.023793.215716
3.04473.215437
3.065743.21516
3.086943.214887
3.108283.214616
3.129773.214347
3.15143.214081
3.173193.213818
3.195133.213556
3.217213.213297
3.239463.213041
3.261853.212786
3.28443.212534
3.307113.212283
3.329973.212035
3.352993.211789
3.376173.211544
3.399513.211302
3.423013.211061
3.446683.210822
3.47053.210585
3.49453.210349
3.518653.210115
3.542983.209883
3.567473.209652
3.592133.209422
3.616973.209194
3.641973.208968
3.667153.208742
3.69253.208518
3.718033.208296
3.743733.208074
3.769613.207853
3.795673.207634
3.821913.207416
3.848333.207198
3.874943.206982
3.901733.206766
3.92873.206552
3.955863.206338
3.983213.206125
4.010743.205913
4.038473.205701
4.066393.20549
4.09453.205279
4.122813.20507
4.151313.20486
4.180013.204651
4.208913.204443
4.2383.204235
4.26733.204027
4.29683.203819
4.326513.203612
4.356423.203405
4.386533.203198
4.416863.202991
4.447393.202785
4.478143.202578
4.50913.202371
4.540273.202164
4.571663.201957
4.603263.20175
4.635083.201543
4.667133.201336
4.699393.201128
4.731883.200919
4.764593.200711
4.797533.200502
4.83073.200292
4.864093.200082
4.897723.199872
4.931583.199661
4.965673.199449
53.199236
5.034573.199023
5.069373.198809
5.104423.198594
5.13973.198378
5.175243.198161
5.211013.197944
5.247043.197725
5.283313.197505
5.319843.197284
5.356613.197062
5.393643.196838
5.430933.196613
5.468483.196387
5.506283.196159
5.544353.19593
5.582683.1957
5.621273.195468
5.660133.195234
5.699263.194999
5.738663.194762
5.778333.194523
5.818283.194282
5.85853.194039
5.8993.193795
5.939793.193548
5.980853.193299
6.02223.193049
6.063833.192795
6.105753.19254
6.147963.192283
6.190463.192023
6.233263.19176
6.276353.191495
6.319743.191227
6.363433.190957
6.407423.190684
6.451713.190408
6.496323.19013
6.541233.189848
6.586453.189564
6.631983.189276
6.677833.188985
6.723993.188691
6.770483.188393
6.817283.188093
6.864413.187788
6.911873.18748
6.959653.187169
7.007763.186854
7.056213.186534
7.104993.186211
7.154113.185884
7.203573.185553
7.253373.185218
7.303513.184878
7.3543.184534
7.404843.184186
7.456033.183833
7.507583.183475
7.559483.183113
7.611743.182745
7.664363.182373
7.717343.181995
7.77073.181612
7.824423.181224
7.878513.18083
7.932973.180431
7.987823.180026
8.043043.179615
8.098643.179198
8.154633.178775
8.2113.178346
8.267773.177911
8.324923.177468
8.382473.17702
8.440423.176564
8.498773.176101
8.557533.175631
8.616693.175154
8.676263.17467
8.736243.174177
8.796633.173677
8.857453.173169
8.918683.172653
8.980343.172128
9.042423.171595
9.104933.171053
9.167873.170503
9.231253.169943
9.295073.169373
9.359333.168794
9.424033.168205
9.489183.167607
9.554783.166998
9.620843.166378
9.687353.165748
9.754323.165106
9.821753.164453
9.889653.163789
9.958023.163113
10.02693.162425
10.09623.161724
10.1663.161011
10.23633.160285
10.3073.159545
10.37833.158792
10.453.158024
10.52233.157242
10.5953.156446
10.66833.155634
10.7423.154807
10.81633.153964
10.8913.153104
10.96633.152228
11.04213.151335
11.11853.150424
11.19533.149495
11.27273.148548
11.35073.147581
11.42913.146595
11.50823.145588
11.58773.144561
11.66783.143513
11.74853.142443
11.82973.14135
11.91153.140234
11.99383.139095
12.07673.137931
12.16023.136742
12.24433.135527
12.32893.134286
12.41423.133017
12.53.13172

Optical transmission calculator

Free-standing sample in vacuum, normal incidence
Method
Transmittance T
—
Reflectance R
—

Fresnel reflection calculator

Direction
Rp
—
Rs
—
R = (Rp+Rs)/2
—
Phase φp
—
Phase φs
—
Brewster angle θB
—
Critical angle θC
—