This paper presents an overview of the growth of Bi2Se3, a prototypical three-dimensional topological insulator, by molecular-beam epitaxy on various substrates. Comparison is made between the growth of Bi2 Se3 (111...This paper presents an overview of the growth of Bi2Se3, a prototypical three-dimensional topological insulator, by molecular-beam epitaxy on various substrates. Comparison is made between the growth of Bi2 Se3 (111) on van der Waals (vdW) and non-vdW substrates, with attention paid to twin suppression and strain. Growth along the [221] direction of Bi2Se3 on InP (001) and GaAs (001) substrates is also discussed.展开更多
High-quality single crystals of Bi_(2)WO_(6) are grown using a flux method.With different flux growth recipes,we aim to control the crystallization temperature to be lower and higher than the ferroelectric transition ...High-quality single crystals of Bi_(2)WO_(6) are grown using a flux method.With different flux growth recipes,we aim to control the crystallization temperature to be lower and higher than the ferroelectric transition temperature,resulting in mono-domain and multi-domain Bi_(2)WO_(6) crystals,respectively.Abundant ferroelastic orthorhombic twin domains are observed in the multi-domain crystals under an optical microscope.PFM studies unveil the 90°polarization change across those ferroelastic domain walls,as well as the absence of 180°ferroelectric domains in the as-grown multi-domain crystals,indicating a high energy cost of 180°ferroelectric domains.Moreover,a 45°tilt of the 90°ferroelectric domain walls is discovered,and this tilt creates a new type of charged 90°ferroelectric walls,which have not been observed in other bulk ferroelectrics.展开更多
基金supported by the Research Grant Council (RGC) of Hong Kong Special Administrative Region for its financial support under the General Research Funds (Grant Nos. 706110 and 706111)the SRFDP and RGCERG Joint Research Scheme sponsored by the RGC of Hong Kong and the Ministry of Education of China (M-HKU709/l2)
文摘This paper presents an overview of the growth of Bi2Se3, a prototypical three-dimensional topological insulator, by molecular-beam epitaxy on various substrates. Comparison is made between the growth of Bi2 Se3 (111) on van der Waals (vdW) and non-vdW substrates, with attention paid to twin suppression and strain. Growth along the [221] direction of Bi2Se3 on InP (001) and GaAs (001) substrates is also discussed.
基金supported by the Center for Quantum Materials Synthesis(cQMS)funded by the Gordon and Betty Moore Foundation’s EPiQS initiative through grant GBMF10104by Rutgers University.
文摘High-quality single crystals of Bi_(2)WO_(6) are grown using a flux method.With different flux growth recipes,we aim to control the crystallization temperature to be lower and higher than the ferroelectric transition temperature,resulting in mono-domain and multi-domain Bi_(2)WO_(6) crystals,respectively.Abundant ferroelastic orthorhombic twin domains are observed in the multi-domain crystals under an optical microscope.PFM studies unveil the 90°polarization change across those ferroelastic domain walls,as well as the absence of 180°ferroelectric domains in the as-grown multi-domain crystals,indicating a high energy cost of 180°ferroelectric domains.Moreover,a 45°tilt of the 90°ferroelectric domain walls is discovered,and this tilt creates a new type of charged 90°ferroelectric walls,which have not been observed in other bulk ferroelectrics.