Topological crystalline insulator(TCI)is one of the symmetry-protected topological states.Any TCI can be deformed into a simple product state of several decoupled two-dimensional(2 D)topologically nontrivial layers in...Topological crystalline insulator(TCI)is one of the symmetry-protected topological states.Any TCI can be deformed into a simple product state of several decoupled two-dimensional(2 D)topologically nontrivial layers in its lattice respecting its crystalline symmetries called the layer construction(LC)limit.In this work,based on first-principles calculations we have revealed that both tetragonal LaSbTe(t-LaSbTe)and orthorhombic LaSbTe(o-LaSbTe)can be interpreted as stacking of 2 D topological insulators in each lattice space.The structural phase transition from t-LaSbTe to o-LaSbTe due to soft phonon modes demonstrates how the real space change can lead to the modification of topological states.Their symmetry-based indicators and topological invariants have been analyzed based on LC.We propose that LaSbTe is an ideal example demonstrating the LC paradigm,which bridges the crystal structures in real space to the band topology in momentum space.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11504117,11674369,11925408,11921004,and11974395)the support from the Foundation of Guizhou Science and Technology Department(Grant No.QKHLHZ20177091)+4 种基金the support from the National Thousand-Young-Talents Programthe CAS Pioneer Hundred Talents Programthe National Natural Science Foundation of Chinathe support from the National Key Research and Development Program of China(Grant Nos.2016YFA0300600,2016YFA0302400,and 2018YFA0305700)the K.C.Wong Education Foundation(Grant No.GJTD-2018-01)。
文摘Topological crystalline insulator(TCI)is one of the symmetry-protected topological states.Any TCI can be deformed into a simple product state of several decoupled two-dimensional(2 D)topologically nontrivial layers in its lattice respecting its crystalline symmetries called the layer construction(LC)limit.In this work,based on first-principles calculations we have revealed that both tetragonal LaSbTe(t-LaSbTe)and orthorhombic LaSbTe(o-LaSbTe)can be interpreted as stacking of 2 D topological insulators in each lattice space.The structural phase transition from t-LaSbTe to o-LaSbTe due to soft phonon modes demonstrates how the real space change can lead to the modification of topological states.Their symmetry-based indicators and topological invariants have been analyzed based on LC.We propose that LaSbTe is an ideal example demonstrating the LC paradigm,which bridges the crystal structures in real space to the band topology in momentum space.
