%0 Journal Article
%T Monolayer Boron Nitride: Hyperspectral Imaging in the Deep Ultraviolet
%+ Laboratoire Charles Coulomb (L2C)
%+ Laboratoire de physique et chimie des nano-objets (LPCNO)
%+ National Institute for Materials Science (NIMS)
%A Rousseau, Adrien
%A Ren, Lei
%A Durand, Alrik
%A Valvin, Pierre
%A Gil, Bernard
%A Watanabe, Kenji
%A Taniguchi, Takashi
%A Urbaszek, Bernhard
%A Marie, Xavier
%A Robert, Cédric
%A Cassabois, Guillaume
%< avec comité de lecture
%@ 1530-6984
%J Nano Letters
%I American Chemical Society
%V 21
%P 10133
%8 2021-12-08
%D 2021
%R 10.1021/acs.nanolett.1c02531
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles
%X The optical response of 2D materials and their heterostructures is the subject of intense research with advanced investigation of the luminescence properties in devices made of exfoliated flakes of few- down to one-monolayer thickness. Despite its prevalence in 2D materials research, hexagonal boron nitride (hBN) remains unexplored in this ultimate regime because of its ultrawide bandgap of about 6 eV and the technical difficulties related to performing microscopy in the deep-ultraviolet domain. Here, we report hyperspectral imaging at wavelengths around 200 nm in exfoliated hBN at low temperature. In monolayer boron nitride, we observe direct-gap emission around 6.1 eV. In marked contrast to transition metal dichalcogenides, the photoluminescence signal is intense in few-layer hBN, a result of the near unity radiative efficiency in indirect-gap multilayer hBN.
%G English
%2 https://hal.science/hal-03451945/document
%2 https://hal.science/hal-03451945/file/exfoliated_ML_hBN_final.pdf
%L hal-03451945
%U https://hal.science/hal-03451945
%~ IRD
%~ UNIV-TLSE3
%~ CNRS
%~ INSA-TOULOUSE
%~ L2C
%~ INC-CNRS
%~ MIPS
%~ UNIV-MONTPELLIER
%~ LPCNO
%~ INSA-GROUPE
%~ TEST-HALCNRS
%~ ANR
%~ FERMI
%~ TOULOUSE-INP
%~ UNIV-UT3
%~ UT3-INP
%~ UT3-TOULOUSEINP
%~ UM-2015-2021
%~ ICT-CHIMIE