The Spectroscopic Atlas of Excitonic Complexes in hBN-Encapsulated S-TMD Monolayers: From Excitons to Oxcitons and Beyond
Abstract
Hexagonal boron nitride (hBN) encapsulation has transformed the optical spectroscopy of semiconducting transition-metal dichalcogenide monolayers (MLs) by suppressing extrinsic disorder and enabling the resolution of an increasingly complex hierarchy of excitonic states. This Review provides a spectroscopy-oriented framework for understanding and identifying excitonic complexes in hBN-encapsulated Mo- and W-based MLs and their alloys. The discussion covers bright and dark excitons, Rydberg states, charged excitons, biexcitons, phonon-assisted replicas, and higher-order Fermi-sea many-body states, including hexcitons and oxcitons, with an emphasis on the experimental signatures that distinguish them. Particular attention is given to the combined use of photoluminescence and absorption-related spectroscopy, electrostatic gating, polarization analysis, excitation-power and temperature dependences, magnetic fields, and time-resolved measurements to establish microscopic assignments. The role of alloying as an additional degree of freedom for engineering the excitonic hierarchy, spin-valley configuration, and magneto-optical response is also highlighted. By organizing the rapidly expanding phenomenology around experimentally accessible fingerprints rather than individual material systems, this Review aims to provide a practical and broadly applicable guide for identifying, comparing, and engineering excitonic states in high-quality two-dimensional semiconductors.
Related
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BibTeX
@misc{molas2026spectroscopic,
title = {{The Spectroscopic Atlas of Excitonic Complexes in hBN-Encapsulated S-TMD Monolayers: From Excitons to Oxcitons and Beyond}},
author = {Maciej R. Molas},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.29081},
eprint = {2610.29081},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.29081},
}
RIS
TY - UNPB
TI - The Spectroscopic Atlas of Excitonic Complexes in hBN-Encapsulated S-TMD Monolayers: From Excitons to Oxcitons and Beyond
AU - Maciej R. Molas
PY - 2026
DA - 2026/10/21
PB - arXiv
DO - 10.48550/arxiv.2610.29081
UR - https://arxiv.org/abs/2610.29081
AB - Hexagonal boron nitride (hBN) encapsulation has transformed the optical spectroscopy of semiconducting transition-metal dichalcogenide monolayers (MLs) by suppressing extrinsic disorder and enabling the resolution of an increasingly complex hierarchy of excitonic states. This Review provides a spectroscopy-oriented framework for understanding and identifying excitonic complexes in hBN-encapsulated Mo- and W-based MLs and their alloys. The discussion covers bright and dark excitons, Rydberg states, charged excitons, biexcitons, phonon-assisted replicas, and higher-order Fermi-sea many-body states, including hexcitons and oxcitons, with an emphasis on the experimental signatures that distinguish them. Particular attention is given to the combined use of photoluminescence and absorption-related spectroscopy, electrostatic gating, polarization analysis, excitation-power and temperature dependences, magnetic fields, and time-resolved measurements to establish microscopic assignments. The role of alloying as an additional degree of freedom for engineering the excitonic hierarchy, spin-valley configuration, and magneto-optical response is also highlighted. By organizing the rapidly expanding phenomenology around experimentally accessible fingerprints rather than individual material systems, this Review aims to provide a practical and broadly applicable guide for identifying, comparing, and engineering excitonic states in high-quality two-dimensional semiconductors.
ER -