Coherent dynamics and mapping of excitons in single-layer MoSe2 and WSe2 at the homogeneous limit

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F20%3A73603968" target="_blank" >RIV/61989592:15310/20:73603968 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216305:26620/20:PU137324

Výsledek na webu

<a href="https://obd.upol.cz/id_publ/333183854" target="_blank" >https://obd.upol.cz/id_publ/333183854</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevMaterials.4.034001" target="_blank" >10.1103/PhysRevMaterials.4.034001</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Coherent dynamics and mapping of excitons in single-layer MoSe2 and WSe2 at the homogeneous limit

Popis výsledku v původním jazyce

We perform coherent nonlinear spectroscopy of excitons in single-layers of MoSe2 and WSe2 encapsulated between thin films of hexagonal boron nitride. Employing four-wave-mixing microscopy we identify virtually disorder-free areas, generating an exciton optical response at the homogeneous limit. Focussing on such areas, we measure exciton homogeneous broadening as a function of environmental factors, namely temperature and exciton density. Exploiting four-wave-mixing imaging, we find that at such locations, nonlinear absorption of the exciton excited states and their coherent couplings can be observed. Using the WSe2 heterostructure, we infer coherence and density dynamics of the exciton 2S state. Owing to its increased radiative lifetime, at low temperatures, the dephasing of the 2S state is longer than of the 1S transition. While scanning various heterostructures across tens of micrometers, we conclude that the disorder, principally induced by strain variations, remain to be present creating spatially varying inhomogeneous broadening.

Název v anglickém jazyce

Coherent dynamics and mapping of excitons in single-layer MoSe2 and WSe2 at the homogeneous limit

Popis výsledku anglicky

We perform coherent nonlinear spectroscopy of excitons in single-layers of MoSe2 and WSe2 encapsulated between thin films of hexagonal boron nitride. Employing four-wave-mixing microscopy we identify virtually disorder-free areas, generating an exciton optical response at the homogeneous limit. Focussing on such areas, we measure exciton homogeneous broadening as a function of environmental factors, namely temperature and exciton density. Exploiting four-wave-mixing imaging, we find that at such locations, nonlinear absorption of the exciton excited states and their coherent couplings can be observed. Using the WSe2 heterostructure, we infer coherence and density dynamics of the exciton 2S state. Owing to its increased radiative lifetime, at low temperatures, the dephasing of the 2S state is longer than of the 1S transition. While scanning various heterostructures across tens of micrometers, we conclude that the disorder, principally induced by strain variations, remain to be present creating spatially varying inhomogeneous broadening.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/LQ1601" target="_blank" >LQ1601: CEITEC 2020</a><br>

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Physical Review Materials

ISSN

2475-9953

e-ISSN

—

Svazek periodika

4

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

"034001-1"-"034001-8"

Kód UT WoS článku

000518538400001

EID výsledku v databázi Scopus

2-s2.0-85083396734