The effect of surface termination on dielectric nonlinearity in potassium sodium niobate thin films

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F25%3A43933652" target="_blank" >RIV/60461373:22310/25:43933652 - isvavai.cz</a>

Výsledek na webu

<a href="https://ceramics.onlinelibrary.wiley.com/doi/10.1111/jace.70084" target="_blank" >https://ceramics.onlinelibrary.wiley.com/doi/10.1111/jace.70084</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1111/jace.70084" target="_blank" >10.1111/jace.70084</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The effect of surface termination on dielectric nonlinearity in potassium sodium niobate thin films

Popis výsledku v původním jazyce

The impact of alkali-rich and alkali-depleted surface terminations on dielectric nonlinearity and ferroelectric properties was investigated in sputtered K0.5Na0.5NbO3 (KNN) films. For the alkali depleted surface termination, a similar to 3 nm thick amorphous interfacial layer was found near the top electrode. The presence of a non-ferroelectric interfacial layer reduces both the net remanent (Pr) and maximum polarization (Pmax) while increasing the coercive field (Ec) in the KNN films. Pmax decreased from 31.5 to 30.3 mu C/cm2, likely due to the reduced electric field in the bulk of the film. The influence of the interfacial layer on dielectric properties was evaluated using a capacitor in series model. After removing the effects of the interfacial layer, the Rayleigh coefficients epsilon init and alpha increased by 11 and 47%, respectively. The interfacial layer has more impact on irreversible domain wall motion than on reversible contributions to the relative permittivity. It is believed that this occurs because a higher concentration of defects, such as VK,Na &apos;$V_{{mathrm{K}},{mathrm{Na}}}&lt;^&gt;{prime}$ or VO&lt;middle dot&gt;&lt;middle dot&gt;$V_{mathrm{O}}&lt;^&gt;{ cdot cdot }$, associated with the alkali-depleted interfacial layer generates internal fields that pin domain walls. Alkali depleted surface terminations also produce a higher pseudo-activation energy for polarization reversal compared to films with alkali rich terminations, with deeper potential wells in the material&apos;s energy landscape.

Název v anglickém jazyce

The effect of surface termination on dielectric nonlinearity in potassium sodium niobate thin films

Popis výsledku anglicky

The impact of alkali-rich and alkali-depleted surface terminations on dielectric nonlinearity and ferroelectric properties was investigated in sputtered K0.5Na0.5NbO3 (KNN) films. For the alkali depleted surface termination, a similar to 3 nm thick amorphous interfacial layer was found near the top electrode. The presence of a non-ferroelectric interfacial layer reduces both the net remanent (Pr) and maximum polarization (Pmax) while increasing the coercive field (Ec) in the KNN films. Pmax decreased from 31.5 to 30.3 mu C/cm2, likely due to the reduced electric field in the bulk of the film. The influence of the interfacial layer on dielectric properties was evaluated using a capacitor in series model. After removing the effects of the interfacial layer, the Rayleigh coefficients epsilon init and alpha increased by 11 and 47%, respectively. The interfacial layer has more impact on irreversible domain wall motion than on reversible contributions to the relative permittivity. It is believed that this occurs because a higher concentration of defects, such as VK,Na &apos;$V_{{mathrm{K}},{mathrm{Na}}}&lt;^&gt;{prime}$ or VO&lt;middle dot&gt;&lt;middle dot&gt;$V_{mathrm{O}}&lt;^&gt;{ cdot cdot }$, associated with the alkali-depleted interfacial layer generates internal fields that pin domain walls. Alkali depleted surface terminations also produce a higher pseudo-activation energy for polarization reversal compared to films with alkali rich terminations, with deeper potential wells in the material&apos;s energy landscape.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20500 - Materials engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

JOURNAL OF THE AMERICAN CERAMIC SOCIETY

ISSN

0002-7820

e-ISSN

1551-2916

Svazek periodika

108

Číslo periodika v rámci svazku

11

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

11

Strana od-do

nestránkováno

Kód UT WoS článku

001526834800001

EID výsledku v databázi Scopus

2-s2.0-105010701233