Optical constants

Refractive index of CuGaS₂ (Copper gallium sulfide)

Boyd et al. 1971: n(o) 0.55–11.5 µm; 20 °C

Data: formula 2
Range: 0.55–11.5 µm
Temperature: 293 K
Optical axis: o
Licence: CC0-1.0

Uniaxial crystal, axes: oe

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 2.7134
Extinction coefficient k: 0

Permittivity ε₁: 7.36255
Permittivity ε₂: 0

Absorption coefficient α: 0 cm⁻¹
Penetration depth δ = λ/(2πk): — nm

Abbe number V_d: —
Chromatic dispersion dn/dλ: -1.08183 µm⁻¹

Group index n_g: 3.34908
Group velocity dispersion: 3147.35 fs²/mm

Dispersion parameter D: -17170.5 ps/(nm·km)
Photon energy: 2.11001 eV

ε = (n + ik)², α = 4πk/λ, n_g = 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

# CuGaS2 (Copper gallium sulfide): Boyd et al. 1971: n(o) 0.55–11.5 µm; 20 °C
cugas2 = ls.fetch_refractiveindex("main", "CuGaS2", "Boyd-20-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cugas2.range_nm)  # (550, 11500) nm
eps = cugas2.eps([633])  # complex permittivity

Downloads 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_df37c3ecfc0d/lightsmith"
cugas2 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(cugas2.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (cugas2/boyd-1971-20-o).

# ... load cugas2 as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=cugas2)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=550, stop_nm=1000, num=81),
)
res = ls.solve(sim)  # exact Mie for a sphere
print(res.q_ext)     # extinction efficiency at each wavelength

Same 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_df37c3ecfc0d/lightsmith?model=drude_lorentz"
cugas2_dl = ls.DrudeLorentz.model_validate(json.load(urllib.request.urlopen(url)))

A dispersive Drude–Lorentz model for time-domain solvers.

Materials guide Open a sphere of it in Studio Quick start Ask the community

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

n^{2} - 1 = 2.9064 + \frac{2.3065 λ^{2}}{λ^{2} - 0.1149} + \frac{1.5479 λ^{2}}{λ^{2} - 738.43}

Valid from 0.55 to 11.5 µm.

Coefficients as stored

C_i	Value
C1	2.9064
C2	2.3065
C3	0.1149
C4	1.5479
C5	738.43

Comments and conditions

Ordinary ray (o); 20 °C

Conditions

temperature: 293 K
direction: o

References

1) G. D. Boyd, H. Kasper, J. H McFee. Linear and nonlinear optical properties of AgGaS₂, CuGaS₂, and CuInS₂, and theory of the wedge technique for the measurement of nonlinear coefficients. IEEE J. Quantum Electron., 7, 563-573 (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

doi:10.1109/jqe.1971.1076588 Linear and nonlinear optical properties of AgGaS&lt;inf&gt;2&lt;/inf&gt;, CuGaS&lt;inf&gt;2&lt;/inf&gt;, and CuInS&lt;inf&gt;2&lt;/inf&gt;, and theory of the wedge technique for the measurement of nonlinear coefficients, IEEE Journal of Quantum Electronics (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. Boyd, H. Kasper and J. McFee. Linear and nonlinear optical properties of AgGaS&lt;inf&gt;2&lt;/inf&gt;, CuGaS&lt;inf&gt;2&lt;/inf&gt;, and CuInS&lt;inf&gt;2&lt;/inf&gt;, and theory of the wedge technique for the measurement of nonlinear coefficients. IEEE Journal of Quantum Electronics, 7, 563-573 (1971), doi:10.1109/jqe.1971.1076588; 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

CuGaS2 (Copper gallium sulfide), Boyd et al. 1971: n(o) 0.55–11.5 µm; 20 °C: n and k versus wavelength
λ (µm)	n
0.55	2.761329
0.554207	2.755139
0.558446	2.74914
0.562717	2.743323
0.567021	2.737681
0.571358	2.732207
0.575728	2.726893
0.580132	2.721734
0.584569	2.716723
0.58904	2.711854
0.593545	2.707122
0.598085	2.702522
0.60266	2.698049
0.607269	2.693698
0.611914	2.689465
0.616594	2.685345
0.62131	2.681335
0.626062	2.67743
0.630851	2.673627
0.635676	2.669922
0.640538	2.666312
0.645437	2.662794
0.650374	2.659364
0.655348	2.65602
0.660361	2.652759
0.665412	2.649578
0.670501	2.646475
0.67563	2.643446
0.680797	2.640491
0.686004	2.637606
0.691251	2.634789
0.696538	2.632039
0.701866	2.629353
0.707234	2.626729
0.712644	2.624166
0.718094	2.621661
0.723587	2.619213
0.729121	2.61682
0.734698	2.614481
0.740317	2.612194
0.74598	2.609958
0.751686	2.607771
0.757435	2.605632
0.763228	2.603539
0.769066	2.601492
0.774948	2.599489
0.780875	2.597528
0.786848	2.595609
0.792866	2.593731
0.798931	2.591893
0.805041	2.590092
0.811199	2.58833
0.817403	2.586604
0.823655	2.584913
0.829955	2.583257
0.836303	2.581635
0.8427	2.580045
0.849145	2.578488
0.85564	2.576962
0.862185	2.575467
0.868779	2.574002
0.875424	2.572565
0.88212	2.571157
0.888867	2.569777
0.895665	2.568423
0.902516	2.567096
0.909419	2.565795
0.916375	2.564519
0.923384	2.563267
0.930446	2.56204
0.937563	2.560836
0.944734	2.559654
0.95196	2.558496
0.959241	2.557359
0.966578	2.556243
0.973971	2.555148
0.98142	2.554074
0.988927	2.553019
0.996491	2.551984
1.00411	2.550969
1.01179	2.549972
1.01953	2.548993
1.02733	2.548032
1.03519	2.547088
1.0431	2.546162
1.05108	2.545252
1.05912	2.544359
1.06722	2.543481
1.07539	2.54262
1.08361	2.541774
1.0919	2.540942
1.10025	2.540126
1.10867	2.539324
1.11715	2.538536
1.12569	2.537761
1.1343	2.537001
1.14298	2.536253
1.15172	2.535519
1.16053	2.534797
1.1694	2.534088
1.17835	2.533391
1.18736	2.532705
1.19644	2.532032
1.20559	2.53137
1.21482	2.530719
1.22411	2.53008
1.23347	2.529451
1.2429	2.528832
1.25241	2.528224
1.26199	2.527627
1.27164	2.527039
1.28137	2.526461
1.29117	2.525892
1.30104	2.525333
1.311	2.524783
1.32102	2.524242
1.33113	2.52371
1.34131	2.523187
1.35157	2.522672
1.36191	2.522166
1.37232	2.521668
1.38282	2.521177
1.39339	2.520695
1.40405	2.52022
1.41479	2.519753
1.42561	2.519293
1.43652	2.518841
1.4475	2.518396
1.45858	2.517958
1.46973	2.517526
1.48097	2.517102
1.4923	2.516683
1.50371	2.516272
1.51522	2.515867
1.5268	2.515468
1.53848	2.515075
1.55025	2.514688
1.56211	2.514307
1.57406	2.513932
1.58609	2.513562
1.59823	2.513198
1.61045	2.51284
1.62277	2.512487
1.63518	2.512139
1.64769	2.511796
1.66029	2.511458
1.67299	2.511125
1.68578	2.510797
1.69868	2.510474
1.71167	2.510156
1.72476	2.509842
1.73795	2.509532
1.75125	2.509227
1.76464	2.508926
1.77814	2.50863
1.79174	2.508337
1.80544	2.508049
1.81925	2.507765
1.83317	2.507484
1.84719	2.507208
1.86132	2.506935
1.87555	2.506666
1.8899	2.5064
1.90435	2.506138
1.91892	2.505879
1.9336	2.505624
1.94839	2.505372
1.96329	2.505124
1.97831	2.504878
1.99344	2.504636
2.00868	2.504397
2.02405	2.504161
2.03953	2.503927
2.05513	2.503697
2.07085	2.503469
2.08669	2.503244
2.10265	2.503022
2.11873	2.502802
2.13493	2.502585
2.15126	2.502371
2.16772	2.502159
2.1843	2.501949
2.201	2.501742
2.21784	2.501537
2.2348	2.501334
2.2519	2.501134
2.26912	2.500935
2.28647	2.500739
2.30396	2.500544
2.32159	2.500352
2.33934	2.500162
2.35723	2.499973
2.37526	2.499786
2.39343	2.499601
2.41174	2.499418
2.43018	2.499237
2.44877	2.499057
2.4675	2.498879
2.48637	2.498702
2.50539	2.498527
2.52455	2.498353
2.54386	2.498181
2.56332	2.49801
2.58293	2.497841
2.60268	2.497672
2.62259	2.497505
2.64265	2.497339
2.66286	2.497175
2.68323	2.497011
2.70375	2.496849
2.72443	2.496688
2.74527	2.496527
2.76627	2.496368
2.78743	2.496209
2.80875	2.496052
2.83023	2.495895
2.85188	2.495739
2.87369	2.495584
2.89567	2.495429
2.91782	2.495275
2.94013	2.495122
2.96262	2.49497
2.98528	2.494818
3.00811	2.494667
3.03112	2.494516
3.05431	2.494365
3.07767	2.494215
3.10121	2.494065
3.12493	2.493916
3.14883	2.493767
3.17291	2.493619
3.19718	2.49347
3.22164	2.493322
3.24628	2.493174
3.27111	2.493026
3.29613	2.492878
3.32134	2.49273
3.34674	2.492582
3.37234	2.492434
3.39813	2.492286
3.42412	2.492138
3.45031	2.49199
3.4767	2.491842
3.50329	2.491693
3.53009	2.491545
3.55709	2.491396
3.5843	2.491246
3.61171	2.491096
3.63934	2.490946
3.66717	2.490796
3.69522	2.490645
3.72348	2.490493
3.75196	2.490341
3.78066	2.490188
3.80958	2.490035
3.83872	2.489881
3.86808	2.489726
3.89766	2.489571
3.92747	2.489415
3.95751	2.489258
3.98778	2.4891
4.01828	2.488941
4.04902	2.488781
4.07999	2.488621
4.11119	2.488459
4.14264	2.488296
4.17432	2.488132
4.20625	2.487967
4.23842	2.487801
4.27084	2.487633
4.30351	2.487464
4.33642	2.487294
4.36959	2.487122
4.40301	2.48695
4.43669	2.486775
4.47062	2.486599
4.50482	2.486422
4.53927	2.486243
4.57399	2.486062
4.60898	2.485879
4.64423	2.485695
4.67975	2.485509
4.71555	2.485321
4.75161	2.485131
4.78796	2.48494
4.82458	2.484746
4.86148	2.48455
4.89866	2.484352
4.93613	2.484152
4.97388	2.48395
5.01193	2.483745
5.05026	2.483538
5.08889	2.483329
5.12781	2.483117
5.16703	2.482903
5.20655	2.482686
5.24638	2.482466
5.2865	2.482244
5.32694	2.482019
5.36768	2.481791
5.40874	2.48156
5.45011	2.481327
5.49179	2.48109
5.5338	2.48085
5.57612	2.480607
5.61877	2.480361
5.66175	2.480112
5.70505	2.479859
5.74869	2.479602
5.79266	2.479342
5.83696	2.479079
5.88161	2.478812
5.92659	2.478541
5.97192	2.478266
6.0176	2.477987
6.06363	2.477704
6.11001	2.477418
6.15674	2.477127
6.20383	2.476831
6.25128	2.476531
6.29909	2.476227
6.34727	2.475918
6.39582	2.475605
6.44474	2.475287
6.49403	2.474964
6.5437	2.474635
6.59375	2.474302
6.64419	2.473964
6.69501	2.47362
6.74621	2.473271
6.79781	2.472917
6.84981	2.472556
6.9022	2.47219
6.95499	2.471818
7.00819	2.471441
7.06179	2.471057
7.1158	2.470666
7.17023	2.470269
7.22507	2.469866
7.28033	2.469456
7.33602	2.469039
7.39213	2.468616
7.44867	2.468185
7.50564	2.467746
7.56305	2.467301
7.62089	2.466847
7.67918	2.466386
7.73792	2.465917
7.7971	2.46544
7.85674	2.464955
7.91683	2.464461
7.97738	2.463959
8.0384	2.463447
8.09988	2.462927
8.16184	2.462397
8.22426	2.461858
8.28717	2.461309
8.35055	2.46075
8.41442	2.460181
8.47878	2.459602
8.54363	2.459013
8.60898	2.458412
8.67483	2.4578
8.74118	2.457177
8.80803	2.456543
8.8754	2.455896
8.94329	2.455238
9.01169	2.454567
9.08062	2.453883
9.15007	2.453187
9.22006	2.452477
9.29058	2.451753
9.36164	2.451015
9.43324	2.450263
9.50539	2.449497
9.5781	2.448715
9.65136	2.447918
9.72517	2.447106
9.79956	2.446277
9.87451	2.445431
9.95004	2.444569
10.0261	2.443689
10.1028	2.442791
10.1801	2.441875
10.258	2.440941
10.3364	2.439987
10.4155	2.439013
10.4951	2.438019
10.5754	2.437004
10.6563	2.435968
10.7378	2.43491
10.8199	2.433829
10.9027	2.432725
10.9861	2.431598
11.0701	2.430446
11.1548	2.429268
11.2401	2.428065
11.3261	2.426836
11.4127	2.425579
11.5	2.424294

Optical transmission calculator

Free-standing sample in vacuum, normal incidence

Transmittance T: —
Reflectance R: —

Fresnel reflection calculator

R_p: —
R_s: —
R = (R_p+R_s)/2: —
Phase φ_p: —
Phase φ_s: —
Brewster angle θ_B: —
Critical angle θ_C: —

CuGaS₂ (Copper gallium sulfide): all datasets

About CuGaS2 (Copper gallium sulfide)

Copper gallium sulfide (CuGaS₂) is a ternary compound semiconductor that exhibits a chalcopyrite crystal structure. This material is notable for its non-linear optical properties and is frequently employed in non-linear frequency conversion applications such as second-harmonic generation and parametric down-conversion. Its large non-linear coefficients and extensive phase-matching capabilities make it an ideal choice for infrared and mid-infrared applications. The material also boasts high thermal conductivity and damage threshold, which lends itself well to high-power optical systems. While not as commonly used as some other non-linear optical materials, copper gallium sulfide remains a specialized choice for applications requiring efficient non-linear frequency conversion, particularly in the infrared spectrum.

More about CuGaS2 (Copper gallium sulfide) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/main/CuGaS2/nk/Boyd-20-o.yml
ID: ds_df37c3ecfc0d
API: /v1/datasets/ds_df37c3ecfc0d

Plot