Optical constants

Refractive index of Al2O3 (Aluminium sesquioxide, Sapphire, Alumina)

Malitson and Dodge 1972: α-Al2O3 (Sapphire); n(o) 0.20–5.0 µm

Data
formula 1
Range
0.2–5 µm
Temperature
293 K
Optical axis
o
State
crystalline
Licence
CC0-1.0

Uniaxial crystal, axes: oe

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.2–5 µm
Refractive index n
1.76817
Extinction coefficient k
0
Permittivity ε1
3.12643
Permittivity ε2
0
Absorption coefficient α
0 cm⁻¹
Penetration depth δ = λ/(2πk)
— nm
Abbe number Vd
72.309
Chromatic dispersion dn/dλ
-0.055289 µm⁻¹
Group index ng
1.80066
Group velocity dispersion
91.1743 fs²/mm
Dispersion parameter D
-497.404 ps/(nm·km)
Photon energy
2.11001 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

# Al2O3 (Aluminium sesquioxide, Sapphire, Alumina): Malitson and Dodge 1972: α-Al2O3 (Sapphire); n(o) 0.20–5.0 µm
al2o3 = ls.fetch_refractiveindex("main", "Al2O3", "Malitson-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(al2o3.range_nm)  # (200, 5000) nm
eps = al2o3.eps([633])  # 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 (formula 1), λ in µm
n2−1=1.4313493λ2λ2−0.07266312+0.65054713λ2λ2−0.11932422+5.3414021λ2λ2−18.0282512

Valid from 0.2 to 5.0 µm.

Coefficients as stored
CiValue
C10.0
C21.4313493
C30.0726631
C40.65054713
C50.1193242
C65.3414021
C718.028251

Comments and conditions

Synthetic sapphire, Ordinary ray (o), 20 °C

Conditions

temperature
293 K
direction
o

References

1) I. H. Malitson and M. J. Dodge. Refractive index and birefringence of synthetic sapphire. J. Opt. Soc. Am. 62, 1405 (1972)
2) M. J. Dodge. "Refractive index" in Handbook of Laser Science and Technology, Volume IV, Optical Materials: Part 2, CRC Press, Boca Raton, 1986, p. 30
* Ref. 1 is a talk abstract in a conference program; Ref. 2 provides a dispersion formula

Cite

I. H. Malitson and M. J. Dodge. Refractive index and birefringence of synthetic sapphire. J. Opt. Soc. Am. 62, 1405 (1972); 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
Al2O3 (Aluminium sesquioxide, Sapphire, Alumina), Malitson and Dodge 1972: α-Al2O3 (Sapphire); n(o) 0.20–5.0 µm: n and k versus wavelength
λ (µm)n
0.21.912709
0.201621.909342
0.2032531.906066
0.2048991.90288
0.2065591.899779
0.2082321.896761
0.2099191.893822
0.2116191.890959
0.2133331.88817
0.2150611.885453
0.2168031.882804
0.218561.880221
0.220331.877703
0.2221151.875247
0.2239141.87285
0.2257271.870512
0.2275561.86823
0.2293991.866002
0.2312571.863827
0.233131.861704
0.2350191.859629
0.2369221.857603
0.2388411.855623
0.2407761.853688
0.2427261.851797
0.2446921.849948
0.2466741.848141
0.2486721.846374
0.2506871.844646
0.2527171.842956
0.2547641.841303
0.2568281.839685
0.2589081.838102
0.2610051.836554
0.2631191.835038
0.2652511.833554
0.2673991.832102
0.2695651.83068
0.2717481.829287
0.273951.827924
0.2761691.826588
0.2784061.82528
0.2806611.823999
0.2829341.822744
0.2852261.821514
0.2875361.820309
0.2898651.819128
0.2922131.817971
0.294581.816836
0.2969661.815724
0.2993711.814634
0.3017961.813566
0.3042411.812518
0.3067051.81149
0.309191.810483
0.3116941.809495
0.3142191.808526
0.3167641.807575
0.319331.806643
0.3219161.805728
0.3245241.804831
0.3271521.80395
0.3298021.803086
0.3324741.802238
0.3351671.801406
0.3378821.80059
0.3406181.799788
0.3433771.799001
0.3461591.798229
0.3489631.797471
0.3517891.796727
0.3546391.795996
0.3575111.795279
0.3604071.794574
0.3633261.793882
0.3662691.793203
0.3692361.792536
0.3722271.79188
0.3752421.791236
0.3782821.790604
0.3813461.789983
0.3844341.789372
0.3875481.788773
0.3906881.788184
0.3938521.787605
0.3970421.787036
0.4002581.786477
0.40351.785927
0.4067691.785387
0.4100641.784857
0.4133851.784335
0.4167341.783822
0.4201091.783318
0.4235121.782822
0.4269421.782335
0.4304011.781856
0.4338871.781385
0.4374011.780921
0.4409441.780465
0.4445161.780017
0.4481161.779577
0.4517461.779143
0.4554051.778716
0.4590941.778297
0.4628131.777884
0.4665621.777478
0.4703411.777078
0.474151.776685
0.4779911.776298
0.4818631.775917
0.4857661.775542
0.4897011.775173
0.4936671.77481
0.4976661.774453
0.5016971.774101
0.5057611.773754
0.5098571.773413
0.5139871.773077
0.518151.772746
0.5223471.77242
0.5265781.772098
0.5308441.771782
0.5351441.77147
0.5394781.771163
0.5438481.770861
0.5482531.770563
0.5526941.770269
0.5571711.769979
0.5616841.769694
0.5662341.769412
0.570821.769135
0.5754441.768861
0.5801051.768592
0.5848041.768326
0.589541.768063
0.5943161.767804
0.599131.767549
0.6039831.767297
0.6088751.767048
0.6138071.766803
0.6187791.766561
0.6237911.766322
0.6288431.766085
0.6339371.765852
0.6390721.765622
0.6442481.765395
0.6494671.76517
0.6547271.764948
0.6600311.764729
0.6653771.764512
0.6707661.764298
0.67621.764086
0.6816771.763877
0.6871981.76367
0.6927651.763465
0.6983761.763263
0.7040331.763063
0.7097361.762864
0.7154841.762668
0.721281.762474
0.7271221.762282
0.7330121.762091
0.7389491.761902
0.7449351.761716
0.7509691.76153
0.7570521.761347
0.7631841.761165
0.7693651.760985
0.7755971.760806
0.781881.760629
0.7882131.760453
0.7945971.760278
0.8010341.760105
0.8075221.759933
0.8140631.759762
0.8206571.759593
0.8273041.759424
0.8340051.759257
0.8407611.75909
0.8475711.758925
0.8544361.758761
0.8613571.758597
0.8683341.758434
0.8753681.758272
0.8824581.758111
0.8896061.757951
0.8968121.757791
0.9040761.757632
0.9113991.757473
0.9187811.757315
0.9262231.757158
0.9337261.757001
0.9412891.756844
0.9489131.756688
0.95661.756532
0.9643481.756376
0.9721591.756221
0.9800341.756066
0.9879721.75591
0.9959741.755756
1.004041.755601
1.012171.755446
1.020371.755291
1.028641.755136
1.036971.754981
1.045371.754826
1.053841.754671
1.062371.754515
1.070981.754359
1.079651.754203
1.08841.754047
1.097211.75389
1.10611.753733
1.115061.753575
1.124091.753416
1.13321.753258
1.142381.753098
1.151631.752938
1.160961.752777
1.170361.752616
1.179841.752454
1.18941.752291
1.199031.752127
1.208751.751962
1.218541.751796
1.228411.751629
1.238361.751461
1.248391.751292
1.25851.751122
1.268691.750951
1.278971.750779
1.289331.750605
1.299771.75043
1.31031.750253
1.320911.750075
1.331611.749896
1.34241.749715
1.353271.749533
1.364231.749349
1.375281.749163
1.386421.748976
1.397651.748787
1.408981.748596
1.420391.748403
1.431891.748208
1.443491.748012
1.455181.747813
1.466971.747612
1.478851.747409
1.490831.747204
1.502911.746997
1.515081.746787
1.527351.746575
1.539721.74636
1.55221.746143
1.564771.745924
1.577441.745702
1.590221.745477
1.60311.74525
1.616091.745019
1.629181.744786
1.642371.74455
1.655681.744311
1.669091.744069
1.682611.743824
1.696241.743576
1.709981.743324
1.723831.743069
1.737791.742811
1.751871.742549
1.766061.742284
1.780361.742015
1.794781.741742
1.809321.741466
1.823971.741186
1.838751.740902
1.853641.740613
1.868661.740321
1.883791.740025
1.899051.739724
1.914431.739419
1.929941.73911
1.945571.738796
1.961331.738477
1.977221.738154
1.993241.737826
2.009381.737493
2.025661.737156
2.042061.736813
2.05861.736465
2.075281.736111
2.092091.735753
2.109041.735388
2.126121.735019
2.143341.734643
2.16071.734262
2.17821.733875
2.195851.733481
2.213631.733082
2.231561.732676
2.249641.732264
2.267861.731846
2.286231.731421
2.304751.730989
2.323421.73055
2.342241.730104
2.361211.729651
2.380331.729191
2.399621.728724
2.419051.728248
2.438651.727766
2.45841.727275
2.478311.726776
2.498391.726269
2.518621.725754
2.539021.725231
2.559591.724698
2.580321.724157
2.601221.723607
2.622291.723048
2.643531.72248
2.664951.721902
2.686531.721314
2.708291.720717
2.730231.72011
2.752351.719492
2.774641.718864
2.797111.718226
2.819771.717576
2.842611.716916
2.865641.716244
2.888851.715561
2.912251.714866
2.935841.71416
2.959621.713441
2.983591.71271
3.007761.711966
3.032121.71121
3.056681.71044
3.081441.709657
3.10641.70886
3.131561.70805
3.156931.707225
3.18251.706387
3.208271.705533
3.234261.704664
3.260461.70378
3.286871.702881
3.313491.701966
3.340331.701034
3.367391.700086
3.394661.699121
3.422161.698139
3.449881.697139
3.477821.696122
3.505991.695086
3.534391.694032
3.563021.692958
3.591881.691866
3.620981.690753
3.650311.68962
3.679871.688467
3.709681.687293
3.739731.686097
3.770021.68488
3.800561.68364
3.831341.682377
3.862381.681091
3.893661.679781
3.92521.678447
3.956991.677088
3.989051.675704
4.021361.674294
4.053931.672857
4.086771.671394
4.119871.669903
4.153241.668384
4.186881.666836
4.220791.665259
4.254981.663651
4.289451.662013
4.324191.660344
4.359221.658642
4.394531.656908
4.430121.65514
4.466011.653338
4.502181.651501
4.538651.649628
4.575411.647718
4.612471.645771
4.649831.643785
4.68751.641761
4.725471.639696
4.763741.637589
4.802331.635441
4.841231.63325
4.880441.631014
4.919971.628733
4.959831.626406
51.624032

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
—