Optical constants

Refractive index of Ta (Tantalum)

Ordal et al. 1988: n,k 0.667–125 µm

Data: tabulated nk
Range: 0.667–125 µm
Points: 49
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 11.1209
Extinction coefficient k: 50.2975

Permittivity ε₁: -2406.16
Permittivity ε₂: 1118.7

Absorption coefficient α: 692285 cm⁻¹
Penetration depth δ = λ/(2πk): 28.8898 nm

Abbe number V_d: —
Chromatic dispersion dn/dλ: 2.0812 µm⁻¹

Group index n_g: -7.88049
Group velocity dispersion: — fs²/mm

Dispersion parameter D: — ps/(nm·km)
Photon energy: 0.135799 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

# Ta (Tantalum): Ordal et al. 1988: n,k 0.667–125 µm
ta = ls.fetch_refractiveindex("main", "Ta", "Ordal", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(ta.range_nm)  # (667, 125000) nm
eps = ta.eps([9130])  # 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_57e4d92b8dbb/lightsmith"
ta = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(ta.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (ta/ordal-1988).

# ... load ta as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=ta)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=667, 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"]).

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.

References

M. A. Ordal, R. J. Bell, R. W. Alexander, L. A. Newquist, M. R. Querry. Optical properties of Al, Fe, Ti, Ta, W, and Mo at submillimeter wavelengths. Appl. Opt. 27, 1203-1209 (1988)

doi:10.1364/ao.27.001203 Optical properties of Al, Fe, Ti, Ta, W, and Mo at submillimeter wavelengths, Applied Optics (1988)

Cite

Mark A. Ordal, Robert J. Bell, Ralph W. Alexander, Lawrence A. Newquist and Marvin R. Querry. Optical properties of Al, Fe, Ti, Ta, W, and Mo at submillimeter wavelengths. Applied Optics, 27, 1203 (1988), doi:10.1364/ao.27.001203; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

49 rows as published

CSV comma separated TXT tab separated YAML n, k Full database record original YAML All quantities CSV JSON metadata

Ta (Tantalum), Ordal et al. 1988: n,k 0.667–125 µm: n and k versus wavelength
λ (µm)	n	k
0.667	1.4478379	2.3306224
0.714	1.2685432	2.7919609
0.769	1.1466787	3.2384897
0.833	1.073087	3.7362305
0.909	1.0150307	4.2736932
1.0	0.9821499	4.8873028
1.05	0.96032	5.2167868
1.11	0.9253053	5.5894492
1.18	0.9012078	6.0121558
1.25	0.8740663	6.4776281
1.33	0.8414308	7.0171487
1.43	0.8354757	7.6548582
1.54	0.8564461	8.3686838
1.67	0.9019896	9.1771344
1.82	0.960826	10.114648
2.0	1.0326738	11.243595
2.11	1.1067824	11.896174
2.22	1.192353	12.595572
2.35	1.2678805	13.363144
2.5	1.3499202	14.23958
2.67	1.4802727	15.240124
2.86	1.6348171	16.359682
3.08	1.8209204	17.640057
3.33	2.0587589	19.120563
3.64	2.3469537	20.845754
4.0	2.6799222	22.915456
4.44	3.1932058	25.461819
5.0	3.9020861	28.57704
5.71	4.9008382	32.510917
6.67	6.4122619	37.643719
8.0	8.7691085	44.613332
10.0	12.931507	54.673721
11.1	15.61576	59.926459
12.5	19.058763	66.350003
14.3	24.23852	73.949845
16.7	31.493393	82.79423
20.0	41.721911	93.122866
22.2	48.392026	98.921392
25.0	56.42849	105.16669
28.6	66.1388	111.86857
33.3	77.867703	119.08288
40.0	92.016211	127.08528
44.4	100.17673	131.63028
50.0	109.23359	136.82885
57.1	119.43744	143.08774
66.7	131.25365	151.08524
80.0	145.5884	161.9815
100.0	164.07966	177.86128
125.0	184.49663	196.87085

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: —

Ta (Tantalum): all datasets

Experimental data

Models and simulations

Werner et al. 2009: DFT calculations; n,k 0.0176–2.48 µm n,k 0.01759–2.48 µm

About Ta (Tantalum)

Tantalum (Ta) is a dense, hard, grayish-blue metal that is highly corrosion-resistant. It is part of the refractory metals group, which are characterized by their high melting points and resistance to wear, corrosion, and deformation. Due to its inertness, tantalum is often used in the manufacture of medical implants and surgical instruments, ensuring they don't react with bodily fluids. In the electronics industry, tantalum is used to make capacitors, which are key components in many electronic devices, especially mobile phones and computers. Its ability to form a stable oxide layer on its surface, known as tantalum pentoxide, is crucial for this application. Additionally, the metal is used in the production of superalloys for jet engine components, nuclear reactors, and missile parts due to its high-temperature strength and melting point.

More about Ta (Tantalum) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/main/Ta/nk/Ordal.yml
ID: ds_57e4d92b8dbb
API: /v1/datasets/ds_57e4d92b8dbb

Plot