Layer-controlled nonlinear terahertz valleytronics in two-dimensional semimetal and semiconductor PtSe2

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27360%2F23%3A10252689" target="_blank" >RIV/61989100:27360/23:10252689 - isvavai.cz</a>

Alternative codes found

RIV/61989100:27640/23:10252689 RIV/61989100:27740/23:10252689

Result on the web

<a href="https://onlinelibrary.wiley.com/doi/full/10.1002/inf2.12468" target="_blank" >https://onlinelibrary.wiley.com/doi/full/10.1002/inf2.12468</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/inf2.12468" target="_blank" >10.1002/inf2.12468</a>

Result language

angličtina

Original language name

Layer-controlled nonlinear terahertz valleytronics in two-dimensional semimetal and semiconductor PtSe2

Original language description

Platinum diselenide (PtSe2) is a promising two-dimensional (2D) material for the terahertz (THz) range as, unlike other transitionmetal dichalcogenides (TMDs), its bandgap can be uniquely tuned from a semiconductor in the near-infrared to a semimetal with thenumber of atomic layers. This gives the material unique THz photonic properties that can be layer-engineered. Here, we demonstratethat a controlled THz nonlinearity - tuned from monolayer to bulk PtSe2 - can be realised in wafer size polycrystalline PtSe2 throughthe generation of ultrafast photocurrents and the engineering of the bandstructure valleys. This is combined with the PtSe2 layerinteraction with the substrate for a broken material centro-symmetry permitting a second order nonlinearity. Further, we show layerdependent circular dichroism, where the sign of the ultrafast currents and hence the phase of the emitted THz pulse can be controlledthrough the excitation of different bandstructure valleys. In particular, we show that a semimetal has a strong dichroism that is absentin the monolayer and few layer semiconducting limit. The microscopic origins of this TMD bandstructure engineering is highlightedthrough detailed DFT simulations, and shows the circular dichroism can be controlled when PtSe2 becomes a semimetal and when theK-valleys can be excited. As well as showing that PtSe2 is a promising material for THz generation through layer controlled opticalnonlinearities, this work opens up new class of circular dichroism materials beyond the monolayer limit that has been the case oftraditional TMDs, and impacting a range of domains from THz valleytronics, THz spintronics to harmonic generation

Czech name

—

Czech description

—

Type

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

CEP classification

—

OECD FORD branch

10300 - Physical sciences

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

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

Name of the periodical

Infomat

ISSN

2567-3165

e-ISSN

—

Volume of the periodical

5

Issue of the periodical within the volume

11

Country of publishing house

US - UNITED STATES

Number of pages

16

Pages from-to

—

UT code for WoS article

001061365300001

EID of the result in the Scopus database

2-s2.0-85169840330