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arXiv · 2501.17340

Two-dimensional talc as a natural hyperbolic material

Flávio H. Feres·Francisco C. B. Maia·Shu Chen·Rafael A. Mayer·Maximillian Obst·Osama Hatem·Lukas Wehmeier·Tobias Nörenberg·Matheus S. Queiroz·Victor Mazzotti·J. Michael Klopf·Susanne C. Kehr·Lukas M. Eng·Alisson R. Cadore·Rainer Hillenbrand·Raul O. Freitas·Ingrid D. Barcelos
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Abstract

This study demonstrates that two-dimensional talc, a naturally abundant mineral, supports hyperbolic phonon-polaritons (HPhPs) at mid-infrared wavelengths, thus offering a low-cost alternative to synthetic polaritonic materials. Using scattering scanning near-field optical microscopy (s-SNOM) and synchrotron infrared nano spectroscopy (SINS), we reveal tunable HPhP modes in talc flakes of a long lifetime. These results highlight the potential of natural 2D talc crystals to constituting an effective platform for establishing scalable optoelectronic and photonic devices.

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Flávio H. Feres, Francisco C. B. Maia, Shu Chen, Rafael A. Mayer, Maximillian Obst, Osama Hatem, Lukas Wehmeier, Tobias Nörenberg, Matheus S. Queiroz, Victor Mazzotti, J. Michael Klopf, Susanne C. Kehr, Lukas M. Eng, Alisson R. Cadore, Rainer Hillenbrand, Raul O. Freitas, Ingrid D. Barcelos. 2025-01-28. Two-dimensional talc as a natural hyperbolic material. https://doi.org/10.1039/d5nr02966j

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