For the ultrathin two-dimensional(2D)materials and lateral heterojunction,the formation of unstable but elastic ripples is commonly observed but is rarely studied,especially their correlations with different material ...For the ultrathin two-dimensional(2D)materials and lateral heterojunction,the formation of unstable but elastic ripples is commonly observed but is rarely studied,especially their correlations with different material properties.To fil the knowledge gap in this field,thiswork systematicallyexplores transitionmetal dichalcogenides(TMDCs)in a single component and lateral heterojunction with a series of ripple structures.The ripple formation energy is quantitatively classified into the initial elastic strain stage and fracture threshold stage based on Fermi-like distribution.Electronic structures reveal that the formation of ripples is accompanied by electron accumulations from flat surfaces to ripples.By comparing the unilateral,decaying,and bilateral ripples in 2D lateral heterojunction,we confirm that Fermi-like distribution is still valid regardless of the shape of the ripples,where the thermodynamic and electronic properties are modulated by ripples-induced uneven strain.The main features of optical properties are not affected while the sensitivity to ripple-induced strains is distinguished.More importantly,the phonon properties further demonstrate the potential of ripples in promoting thermal conductivity,which are strongly correlated with the optical branch of anion vibrations.This work provides important theoretical guidance for the design and optimization of high-performance optoelectronic devices based on TMDC heterojunctions.展开更多
基金The authors gratefully acknowledge the support from Research Grant Council of Hong Kong(No.15304023)National Natural Science Foundation of China/Research Grant Council of Hong Kong Joint Research Scheme(No.N_PolyU502/21)+2 种基金the funding for Projects of Strategic Importance of The Hong Kong Polytechnic University(No.1-ZE2V)Shenzhen Fundamental Research Scheme General Program(No.JCYJ20220531090807017)Natural Science Foundation of Guangdong Province(No.2023A1515012219).
文摘For the ultrathin two-dimensional(2D)materials and lateral heterojunction,the formation of unstable but elastic ripples is commonly observed but is rarely studied,especially their correlations with different material properties.To fil the knowledge gap in this field,thiswork systematicallyexplores transitionmetal dichalcogenides(TMDCs)in a single component and lateral heterojunction with a series of ripple structures.The ripple formation energy is quantitatively classified into the initial elastic strain stage and fracture threshold stage based on Fermi-like distribution.Electronic structures reveal that the formation of ripples is accompanied by electron accumulations from flat surfaces to ripples.By comparing the unilateral,decaying,and bilateral ripples in 2D lateral heterojunction,we confirm that Fermi-like distribution is still valid regardless of the shape of the ripples,where the thermodynamic and electronic properties are modulated by ripples-induced uneven strain.The main features of optical properties are not affected while the sensitivity to ripple-induced strains is distinguished.More importantly,the phonon properties further demonstrate the potential of ripples in promoting thermal conductivity,which are strongly correlated with the optical branch of anion vibrations.This work provides important theoretical guidance for the design and optimization of high-performance optoelectronic devices based on TMDC heterojunctions.
