The emerged wurtzite(wz)Al_(1−x)B_(x)N alloy has drawn increasing attention due to its superior ferroelectricity and excellent compatibility with microelectronics.We find that the stability and ferroelectric switching...The emerged wurtzite(wz)Al_(1−x)B_(x)N alloy has drawn increasing attention due to its superior ferroelectricity and excellent compatibility with microelectronics.We find that the stability and ferroelectric switching pathways of wz-Al_(1−x)B_(x)N alloys are affected by the orbital contribution,covalent bond strength,and elastic constant C_(14).As the concentration of B increases,the internal parameter u decreases while the elastic constant C_(14)increases,leading to an increase in spontaneous polarization and a decrease in the polarization switching barrier.The spontaneous polarization,polarization switching barrier,and band gap of wz-Al_(1−x)B_(x)N alloy can be further improved through the application of strain in a specific direction,resulting in a giant ferroelectricity.Additionally,the phase transformation of the wz-Al_(1−x)B_(x)N alloy induced by the increasing B composition can be regarded as a sequential process involving shrinkage,rotation,and deformation of tetrahedron.These findings give a deep understanding of the ferroelectric wz-Al_(1−x)B_(x)N alloy,and provide a guideline for designing a high-performance ferroelectric wz-Al_(1−x)B_(x)N alloy.展开更多
基金supported by the National Key Research and Development Program of China(2021YFA0715600)the National Natural Science Foundation of China(grant 62274125 and 52192611)+1 种基金the Key Research and Development Program of Shaanxi Province(grant 2024GX-YBXM-410)Guangdong Basic and Applied Basic Research Fund(2023A1515030084).The numerical calculations in this paper have been done on the HPC system of Xidian University.
文摘The emerged wurtzite(wz)Al_(1−x)B_(x)N alloy has drawn increasing attention due to its superior ferroelectricity and excellent compatibility with microelectronics.We find that the stability and ferroelectric switching pathways of wz-Al_(1−x)B_(x)N alloys are affected by the orbital contribution,covalent bond strength,and elastic constant C_(14).As the concentration of B increases,the internal parameter u decreases while the elastic constant C_(14)increases,leading to an increase in spontaneous polarization and a decrease in the polarization switching barrier.The spontaneous polarization,polarization switching barrier,and band gap of wz-Al_(1−x)B_(x)N alloy can be further improved through the application of strain in a specific direction,resulting in a giant ferroelectricity.Additionally,the phase transformation of the wz-Al_(1−x)B_(x)N alloy induced by the increasing B composition can be regarded as a sequential process involving shrinkage,rotation,and deformation of tetrahedron.These findings give a deep understanding of the ferroelectric wz-Al_(1−x)B_(x)N alloy,and provide a guideline for designing a high-performance ferroelectric wz-Al_(1−x)B_(x)N alloy.
