Strong localization effects in the photoluminescence of transition metal dichalcogenide heterobilayers

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F21%3A00540945" target="_blank" >RIV/61388955:_____/21:00540945 - isvavai.cz</a>

Result on the web

<a href="http://hdl.handle.net/11104/0318535" target="_blank" >http://hdl.handle.net/11104/0318535</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/2053-1583/abe363" target="_blank" >10.1088/2053-1583/abe363</a>

Result language

angličtina

Original language name

Strong localization effects in the photoluminescence of transition metal dichalcogenide heterobilayers

Original language description

The emergence of various exciton-related effects in transition metal dichalcogenides (TMDC) and their heterostructures has inspired a significant number of studies and brought forth several possible applications. Often, standard photoluminescence (PL) with microscale lateral resolution is utilized to identify and characterize these excitonic phenomena, including interlayer excitons (IEXs). We studied the local PL signatures of van der Waals heterobilayers composed of exfoliated monolayers of the (Mo, W)(S, Se)2 TMDC family with high spatial resolution (down to 30 nm) using tip-enhanced photoluminescence (TEPL) with different orders (top/bottom) and on different substrates. We evidence that in MoS2–WSe2 heterobilayers, other PL signals may appear near the reported energy of the IEX transitions, possibly interfering in the interpretation of the results. The extra signals are only observed locally in small areas where the topography looks distorted. We assign those signals to the PL of the individual monolayers, in which the exciton energy is altered by the local strains caused by the formation of blisters and nanobubbles, and the PL is extremely enhanced due to the decoupling of the layers. We prove that even a single nanobubble as small as 60 nm-hence not optically visible-can induce such a suspicious PL feature in the micro-PL spectrum of an otherwise flat heterobilayer. In contrast, a PL peak, which could be assigned to the interlayer exciton in MoS2-WSe2, is observed at ≈1.0 eV.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10403 - Physical chemistry

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

2D Materials

ISSN

2053-1583

e-ISSN

2053-1583

Volume of the periodical

8

Issue of the periodical within the volume

2

Country of publishing house

GB - UNITED KINGDOM

Number of pages

10

Pages from-to

025028

UT code for WoS article

000621895200001

EID of the result in the Scopus database

2-s2.0-85102562445