When stereochemically-active-lone-pair(SCALP)cations are introduced into chalcogenide systems,it is beneficial to produce a remarkable second-harmonic generation(SHG)response(d_(eff)),but it also causes a narrow band ...When stereochemically-active-lone-pair(SCALP)cations are introduced into chalcogenide systems,it is beneficial to produce a remarkable second-harmonic generation(SHG)response(d_(eff)),but it also causes a narrow band gap(E_(g)),which ultimately results in negative two-photon and free-carrier absorption.Hence,how to obtain a wide E_(g)(>2.33 eV)while maintaining a strong d_(eff)remains a significant challenge in this domain.In this work,Rb is partially replaced by SCALP Pb in the known ternary centrosymmetric(CS)Rb3PS_(4)(space group:Pnma).This results in a quaternary non-centrosymmetric(NCS)RbPbPS_(4)(space group:P212121),which possesses distinct 2D[PbPS_(4)]−layers and Rb+occupies the interlayer spaces as the counter cations.Notably,RbPbPS_(4)exhibits a promising overall performance,including strong d_(eff)(2.5×AgGaS_(2)),wide IR transmittance cutoff edge(up to 18.1μm)along with the large E_(g)(2.75 eV),resulting in an improved laser-induced damage threshold(7.5×AgGaS_(2)).Theoretical calculations further indicated that the favorable balance between strong d_(eff)and large E_(g)in RbPbPS_(4)can be attributed to the synergies of the[PbS7]and[PS_(4)]nonlinear optical(NLO)-active units.This study not only presents a high-performance Pb-based IR-NLO candidate but also underscores the effectiveness of partial substitution of SCALP cations in inducing a CS-to-NCS structural transformation.展开更多
基金supported by the National Natural Science Foundation of China(22175175)Natural Science Foundation of Fujian Province(2022L3092 and 2023H0041)+1 种基金Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR118)the Youth Innovation Promotion Association CAS(2022303).
文摘When stereochemically-active-lone-pair(SCALP)cations are introduced into chalcogenide systems,it is beneficial to produce a remarkable second-harmonic generation(SHG)response(d_(eff)),but it also causes a narrow band gap(E_(g)),which ultimately results in negative two-photon and free-carrier absorption.Hence,how to obtain a wide E_(g)(>2.33 eV)while maintaining a strong d_(eff)remains a significant challenge in this domain.In this work,Rb is partially replaced by SCALP Pb in the known ternary centrosymmetric(CS)Rb3PS_(4)(space group:Pnma).This results in a quaternary non-centrosymmetric(NCS)RbPbPS_(4)(space group:P212121),which possesses distinct 2D[PbPS_(4)]−layers and Rb+occupies the interlayer spaces as the counter cations.Notably,RbPbPS_(4)exhibits a promising overall performance,including strong d_(eff)(2.5×AgGaS_(2)),wide IR transmittance cutoff edge(up to 18.1μm)along with the large E_(g)(2.75 eV),resulting in an improved laser-induced damage threshold(7.5×AgGaS_(2)).Theoretical calculations further indicated that the favorable balance between strong d_(eff)and large E_(g)in RbPbPS_(4)can be attributed to the synergies of the[PbS7]and[PS_(4)]nonlinear optical(NLO)-active units.This study not only presents a high-performance Pb-based IR-NLO candidate but also underscores the effectiveness of partial substitution of SCALP cations in inducing a CS-to-NCS structural transformation.
