Biaxial strain tuning of excitons in monolayer MoSe$_2$ by high-temperature physical vapor deposition

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Patel, S., Faltermeier, T., Puri, S., Rodriguez, R., Reynolds, K., Davari, S., Churchill, H. O. H., Borys, N. J., Nakamura, H.
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912175828762624
author Patel, S.
Faltermeier, T.
Puri, S.
Rodriguez, R.
Reynolds, K.
Davari, S.
Churchill, H. O. H.
Borys, N. J.
Nakamura, H.
author_facet Patel, S.
Faltermeier, T.
Puri, S.
Rodriguez, R.
Reynolds, K.
Davari, S.
Churchill, H. O. H.
Borys, N. J.
Nakamura, H.
contents We present strain tuning of excitonic emission in monolayer MoSe$_2$ by using a high-temperature physical vapor deposition (PVD). The use of two amorphous substrates, Si$_{3}$N$_{4}$ and SiO$_{2}$, provides two setpoints to induce distinct amounts of \textit{biaxial} tensile strain determined by a thermal expansion mismatch between the monolayer and the substrate. The tuning rate of the $A$-exciton transition energy is found to be 103 meV/\% by photoluminescence (PL), which represents the highest value realized by biaxial strain in transition metal dichalcogenides. The biaxial nature of the tensile strain is confirmed by polarization-resolved second harmonic generation, which reveals unperturbed in-plane three-fold symmetry of the monolayer. Furthermore, a softening of $A_\mathrm{1g}$ out-of-plane lattice vibration is identified in the Raman spectroscopy, which is known to be insignificant for uniaxial strain. Concomitantly, PL mapping of our PVD monolayers demonstrates (i) larger strain occurs in the interior of the mono-domain islands compared to the edges and (ii) the absence of island-size dependence in the magnitude of induced strain. Our results demonstrate an effective path towards strain engineering of excitons by using growth substrates, which holds great promise as a building block for future optoelectronic applications.
format Preprint
id arxiv_https___arxiv_org_abs_2408_15469
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Biaxial strain tuning of excitons in monolayer MoSe$_2$ by high-temperature physical vapor deposition
Patel, S.
Faltermeier, T.
Puri, S.
Rodriguez, R.
Reynolds, K.
Davari, S.
Churchill, H. O. H.
Borys, N. J.
Nakamura, H.
Materials Science
Mesoscale and Nanoscale Physics
We present strain tuning of excitonic emission in monolayer MoSe$_2$ by using a high-temperature physical vapor deposition (PVD). The use of two amorphous substrates, Si$_{3}$N$_{4}$ and SiO$_{2}$, provides two setpoints to induce distinct amounts of \textit{biaxial} tensile strain determined by a thermal expansion mismatch between the monolayer and the substrate. The tuning rate of the $A$-exciton transition energy is found to be 103 meV/\% by photoluminescence (PL), which represents the highest value realized by biaxial strain in transition metal dichalcogenides. The biaxial nature of the tensile strain is confirmed by polarization-resolved second harmonic generation, which reveals unperturbed in-plane three-fold symmetry of the monolayer. Furthermore, a softening of $A_\mathrm{1g}$ out-of-plane lattice vibration is identified in the Raman spectroscopy, which is known to be insignificant for uniaxial strain. Concomitantly, PL mapping of our PVD monolayers demonstrates (i) larger strain occurs in the interior of the mono-domain islands compared to the edges and (ii) the absence of island-size dependence in the magnitude of induced strain. Our results demonstrate an effective path towards strain engineering of excitons by using growth substrates, which holds great promise as a building block for future optoelectronic applications.
title Biaxial strain tuning of excitons in monolayer MoSe$_2$ by high-temperature physical vapor deposition
topic Materials Science
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2408.15469