Optical constants
Refractive index of PtSe2 (Platinum diselenide)
Tharrault et al. 2025: 6L film; n,k 0.416–1.54 µm
- Data
- tabulated nk
- Range
- 0.4154–1.54 µm
- Points
- 108
- State
- crystalline
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 4.40532
- Extinction coefficient k
- 2.82693
- Permittivity ε1
- 11.4153
- Permittivity ε2
- 24.9071
- Absorption coefficient α
- 604566 cm⁻¹
- Penetration depth δ = λ/(2πk)
- 33.0816 nm
- Abbe number Vd
- —
- Chromatic dispersion dn/dλ
- 0.931408 µm⁻¹
- Group index ng
- 3.85802
- Group velocity dispersion
- — fs²/mm
- Dispersion parameter D
- — 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
# PtSe2 (Platinum diselenide): Tharrault et al. 2025: 6L film; n,k 0.416–1.54 µm
ptse2 = ls.fetch_refractiveindex("main", "PtSe2", "Tharrault-6L", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(ptse2.range_nm) # (415.36, 1539.99) nm
eps = ptse2.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_48cdffcbc4ff/lightsmith"
ptse2 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(ptse2.source) # citation and provenance travel with the data
Any dataset here, as the library's Tabulated material (ptse2/tharrault-2025-6l).
# ... load ptse2 as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=ptse2)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=416, 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"]).
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.
Comments and conditions
References
- doi:10.1103/physrevlett.134.066901 Optical Absorption in Indirect Semiconductor to Semimetal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>PtSe</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> Arises from Direct Transitions, Physical Review Letters (2025)
Cite
Marin Tharrault et al.. Optical Absorption in Indirect Semiconductor to Semimetal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>PtSe</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> Arises from Direct Transitions. Physical Review Letters, 134, 066901 (2025), doi:10.1103/physrevlett.134.066901; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)
Data
108 rows as published| λ (µm) | n | k |
|---|---|---|
| 0.41536 | 4.13675 | 2.00197 |
| 0.41816 | 4.10782 | 2.05799 |
| 0.421 | 4.11882 | 2.07866 |
| 0.42388 | 4.08733 | 2.14622 |
| 0.4268 | 4.06161 | 2.20938 |
| 0.42975 | 4.0729 | 2.22951 |
| 0.43275 | 4.06998 | 2.25526 |
| 0.4358 | 4.07854 | 2.28079 |
| 0.43888 | 4.09105 | 2.29187 |
| 0.44201 | 4.10159 | 2.30928 |
| 0.44519 | 4.12374 | 2.31225 |
| 0.44841 | 4.11162 | 2.35371 |
| 0.45167 | 4.13083 | 2.37064 |
| 0.45499 | 4.12681 | 2.40699 |
| 0.45835 | 4.12353 | 2.42903 |
| 0.46177 | 4.12242 | 2.46322 |
| 0.46523 | 4.14218 | 2.47279 |
| 0.46875 | 4.15368 | 2.48987 |
| 0.47232 | 4.16211 | 2.5135 |
| 0.47595 | 4.18012 | 2.52159 |
| 0.47963 | 4.18859 | 2.54221 |
| 0.48337 | 4.19702 | 2.55929 |
| 0.48717 | 4.20823 | 2.57102 |
| 0.49103 | 4.22079 | 2.57793 |
| 0.49495 | 4.22871 | 2.58603 |
| 0.49893 | 4.25714 | 2.58761 |
| 0.50298 | 4.27733 | 2.59384 |
| 0.50709 | 4.28 | 2.61343 |
| 0.51128 | 4.29091 | 2.62178 |
| 0.51553 | 4.30281 | 2.6316 |
| 0.51985 | 4.31257 | 2.64546 |
| 0.52425 | 4.32018 | 2.65525 |
| 0.52872 | 4.32613 | 2.67103 |
| 0.53327 | 4.34051 | 2.67773 |
| 0.53789 | 4.34955 | 2.69117 |
| 0.5426 | 4.35489 | 2.70329 |
| 0.54739 | 4.37248 | 2.71099 |
| 0.55227 | 4.38869 | 2.7162 |
| 0.55723 | 4.39779 | 2.72506 |
| 0.56229 | 4.37126 | 2.76312 |
| 0.56743 | 4.36968 | 2.77996 |
| 0.57268 | 4.36483 | 2.80842 |
| 0.57801 | 4.35193 | 2.84612 |
| 0.58346 | 4.40146 | 2.81024 |
| 0.589 | 4.40662 | 2.83258 |
| 0.59465 | 4.43353 | 2.81972 |
| 0.60041 | 4.44141 | 2.84725 |
| 0.60628 | 4.37022 | 2.95909 |
| 0.61227 | 4.41025 | 2.95866 |
| 0.61838 | 4.41521 | 3.00522 |
| 0.62461 | 4.44552 | 3.01553 |
| 0.63096 | 4.49176 | 3.03276 |
| 0.63745 | 4.51682 | 3.05723 |
| 0.64407 | 4.56701 | 3.05651 |
| 0.65084 | 4.63348 | 3.03699 |
| 0.65774 | 4.65751 | 3.06623 |
| 0.66479 | 4.62953 | 3.14398 |
| 0.672 | 4.65728 | 3.17376 |
| 0.67937 | 4.73261 | 3.12611 |
| 0.68689 | 4.69462 | 3.18861 |
| 0.69459 | 4.75952 | 3.15153 |
| 0.70246 | 4.78148 | 3.14968 |
| 0.71051 | 4.82501 | 3.13904 |
| 0.71875 | 4.75858 | 3.25708 |
| 0.72718 | 4.8413 | 3.22648 |
| 0.73581 | 4.89566 | 3.25705 |
| 0.74465 | 4.97799 | 3.25606 |
| 0.7537 | 5.01073 | 3.32183 |
| 0.76298 | 5.08519 | 3.34782 |
| 0.77249 | 5.17943 | 3.35695 |
| 0.78223 | 5.27711 | 3.36221 |
| 0.79223 | 5.38615 | 3.31827 |
| 0.80249 | 5.45833 | 3.32557 |
| 0.81301 | 5.56685 | 3.2735 |
| 0.82382 | 5.66149 | 3.19268 |
| 0.83491 | 5.77091 | 3.09683 |
| 0.84631 | 5.84609 | 3.0065 |
| 0.85802 | 5.95858 | 2.85538 |
| 0.87006 | 5.99872 | 2.76858 |
| 0.88245 | 6.06849 | 2.6252 |
| 0.89519 | 6.0997 | 2.53003 |
| 0.90831 | 6.12961 | 2.42201 |
| 0.92182 | 6.17039 | 2.30036 |
| 0.93573 | 6.19586 | 2.19862 |
| 0.95007 | 6.24749 | 2.06636 |
| 0.96486 | 6.24064 | 1.9605 |
| 0.98011 | 6.28388 | 1.80094 |
| 0.99586 | 6.29899 | 1.66678 |
| 1.01212 | 6.3173 | 1.53242 |
| 1.02891 | 6.31716 | 1.44819 |
| 1.08283 | 6.21505 | 1.14813 |
| 1.10208 | 6.2204 | 1.06203 |
| 1.12203 | 6.17973 | 0.99676 |
| 1.14271 | 6.14782 | 0.93001 |
| 1.16417 | 6.12103 | 0.85567 |
| 1.18645 | 6.1015 | 0.79696 |
| 1.2096 | 6.05285 | 0.75824 |
| 1.23367 | 6.00164 | 0.73609 |
| 1.2586 | 5.95881 | 0.70967 |
| 1.28468 | 5.86865 | 0.71786 |
| 1.31186 | 5.80665 | 0.70151 |
| 1.34022 | 5.76935 | 0.68084 |
| 1.36984 | 5.75653 | 0.66154 |
| 1.40079 | 5.71361 | 0.62712 |
| 1.43318 | 5.65247 | 0.63095 |
| 1.46709 | 5.60928 | 0.62664 |
| 1.50266 | 5.58083 | 0.59987 |
| 1.53999 | 5.58241 | 0.56287 |
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
- —
6L CVT-grown exfoliated crystal. The optical indexes are computed from the 2D surface conductivity using σ2D·Z0 = −2πi·(t/λ)·(εr−1), where Z0 is the impedance of free space, i the imaginary unit, t the equivalent layered stack thickness and λ the free space wavelength. We use t = NL t0 with t0 = 5.1 Å the single layer thickness. The measurement method accuratly determines Im{εr} = 2nk, but only Re{εr} = n2 - k2 as long as the optical absorption is non-zero.