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2Broadband optical properties of anisotropic palladium diselenide
G. Ermolaev12, A. Slavich1, M. Tatmyshevskiy1, G. Tselikov1,2, N. Pak1*, D. Grudinin1, I. Kruglov1, A. Arsenin1'2
1- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Dolgoprudny, Russia 2- Emerging Technologies Research Center, XPANCEO, Dubai Investment Park First, Dubai, United Arab
Emirates
* pak. nv@phystech. edu
Noble metal dichalcogenides (NMDCs) are distinguished among other advanced materials because of their strong layer-dependence of optical properties and interlayer interaction [1,2]. A promising example of NMDCs is a high refractive index PdSe2. This material has practical application due to impressive physical properties [2-4]. PdSe2-based heterostructures can be applied to polarization resolved photodetectors, field effect transistors, infrared sensors [3,5]. To describe the optical phenomena, on which optoelectronic devices are based, one needs to know refractive index n and excitation coefficient k. Nevertheless, there are few works related to the experimental determination of fundamental optical constants of PdSe2 [2,6], infrared region has not been not studied yet.
In this paper, we investigated broadband optical properties of bulk PdSe2 over a wide range of wavelengths. We measured a refractive index and an extinction coefficient by imaging ellipsometry method. Then we extended optical constants dependency to the far-infrared region according to a theoretical model. To evaluate broadened results, we used experimental data obtained from micro-reflectance and scattering near-field optical microscopy and density functional theory computations. Optical constants obtained in our work are necessary in optics and optoelectronics.
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[6] G. Ermolaev, K. Voronin, D.G. Baranov, et al, Topological phase singularities in atomically thin high-refractive-index materials, Nat. Commun., Vol. 13, No. 2049 (2022).
