Unconventional conductivity increase in multilayer black phosphorus

Kolesnik-Gray M, Meingast L, Siebert M, Unbehaun T, Huf T, Ellrott G, Abellan Saez G, Wild S, Lloret Segura VJ, Mundloch U, Schwarz J, Niebauer M, Szabo M, Rommel M, Hutzler A, Hauke F, Hirsch A, Krstic V (2023)

Publication Type: Journal article

Publication year: 2023

Journal

npj 2D Materials and Applications Nature Research

Book Volume: 7

Article Number: 21

Journal Issue: 1

DOI: 10.1038/s41699-023-00384-2

Abstract

Multilayers of so-called 2D van der Waals materials have gained considerable attention as active components of next-generation electronic and optoelectronic technologies, with semiconducting black phosphorus (BP) regarded as one of the most promising systems. The applicability and performance limits of BP in both stand-alone and heterostructure-based multilayer devices are determined by individual flake charge transport properties, which synergistically depend on the number of layers and the strength of interlayer coupling between those. In this work, we study the DC electrical transport characteristics of high-quality BP field-effect devices within a wide range of flake thicknesses at room temperature. The experimental data show a non-trivial increase in conductivity and hole density with a reduced number of layers while maintaining constant field-effect mobility due to the prevalence of electron–phonon scattering. Based on the solution of the 1D Schrödinger–Poisson equation, we find that the observed phenomena are a direct consequence of non-negligible interlayer coupling, which in turn causes a local redistribution of free charge carriers towards the central layers. Our data show that due to the electrostatic conditions at the flake surfaces, a naturally protected 2D hole gas can be encapsulated in flakes as high as 10 nm, which preserves the bulk-like bandgap and effective carrier masses due to the electrostatic environment.

Authors with CRIS profile

Maria Kolesnik-Gray Chair of Applied Physics Laura Meingast Lehrstuhl für Experimentalphysik Martin Siebert Professur für Angewandte Physik Tim Unbehaun Lehrstuhl für Physik Günter Ellrott Sonderforschungsbereich/Transregio 306/1: Quantenkooperativität von Licht und Materie - QuCoLiMa Gonzalo Abellan Saez Lehrstuhl für Organische Chemie II Stefan Wild Sonderforschungsbereich 953/3 Synthetische Kohlenstoffallotrope Vicente Josep Lloret Segura Lehrstuhl für Organische Chemie II Udo Mundloch Lehrstuhl für Organische Chemie II Julian Schwarz Lehrstuhl für Elektronische Bauelemente Michael Niebauer Lehrstuhl für Elektronische Bauelemente Frank Hauke Lehrstuhl für Organische Chemie II Andreas Hirsch Lehrstuhl für Organische Chemie II Vojislav Krstic Professur für Angewandte Physik

Additional Organisation(s)

FAU Profilzentrum Licht.Materie.Quantentechnologien (FAU LMQ)

Involved external institutions

Fraunhofer-Institut für Integrierte Systeme und Bauelementetechnologie (IISB) DE Germany (DE) Forschungszentrum Jülich / Research Centre Jülich (FZJ) DE Germany (DE)

How to cite

APA:

Kolesnik-Gray, M., Meingast, L., Siebert, M., Unbehaun, T., Huf, T., Ellrott, G.,... Krstic, V. (2023). Unconventional conductivity increase in multilayer black phosphorus. npj 2D Materials and Applications, 7(1). https://doi.org/10.1038/s41699-023-00384-2

MLA:

Kolesnik-Gray, Maria, et al. "Unconventional conductivity increase in multilayer black phosphorus." npj 2D Materials and Applications 7.1 (2023).

BibTeX: Download