There is an immense effort in search for various types of Weyl semimetals, of which the most fundamental phase consists of the minimal number of i.e. two Weyl points, but is hard to engineer in solids. Here we demonst...There is an immense effort in search for various types of Weyl semimetals, of which the most fundamental phase consists of the minimal number of i.e. two Weyl points, but is hard to engineer in solids. Here we demonstrate how such fundamental Weyl semimetal can be realized in a maneuverable optical Raman lattice, with which the three-dimensional(3D) spin-orbit(SO) coupling is synthesised for ultracold atoms. In addition, a new novel Weyl phase with coexisting Weyl nodal points and nodal ring is also predicted here, and is shown to be protected by nontrivial linking numbers. We further propose feasible techniques to precisely resolve 3D Weyl band topology through 2D equilibrium and dynamical measurements. This work leads to the first realization of the most fundamental Weyl semimetal band and the 3D SO coupling for ultracold quantum gases, which are respectively the significant issues in the condensed matter and ultracold atom physics.展开更多
To investigate the band structure is one of the key approaches to study the fundamental properties of a novel material.We report here the precision band mapping of a 2-dimensional(2D) spin-orbit(SO) coupling in an opt...To investigate the band structure is one of the key approaches to study the fundamental properties of a novel material.We report here the precision band mapping of a 2-dimensional(2D) spin-orbit(SO) coupling in an optical lattice.By applying the microwave spin-injection spectroscopy, the band structure and spin-polarization distribution are achieved simultaneously.The band topology is also addressed with observing the band gap close and re-open at the Dirac points.Furthermore, the lattice depth and the Raman coupling strength are precisely calibrated with relative errors in the order of 10^(-3).Our approach could also be applied for exploring the exotic topological phases with even higher dimensional system.展开更多
基金supported by the National Natural Science Foundation of China (11825401, 11761161003, and 11921005)the National Key R&D Program of China (2016YFA0301604)Strategic Priority Research Program of CAS (XDB28000000)。
文摘There is an immense effort in search for various types of Weyl semimetals, of which the most fundamental phase consists of the minimal number of i.e. two Weyl points, but is hard to engineer in solids. Here we demonstrate how such fundamental Weyl semimetal can be realized in a maneuverable optical Raman lattice, with which the three-dimensional(3D) spin-orbit(SO) coupling is synthesised for ultracold atoms. In addition, a new novel Weyl phase with coexisting Weyl nodal points and nodal ring is also predicted here, and is shown to be protected by nontrivial linking numbers. We further propose feasible techniques to precisely resolve 3D Weyl band topology through 2D equilibrium and dynamical measurements. This work leads to the first realization of the most fundamental Weyl semimetal band and the 3D SO coupling for ultracold quantum gases, which are respectively the significant issues in the condensed matter and ultracold atom physics.
基金supported by the National Key R&D Program of China (2016YFA0301601 and 2016YFA0301604)the National Natural Science Foundation of China (11674301, 11761161003, and 11625522)the Thousand-Young-Talent Program of China
文摘To investigate the band structure is one of the key approaches to study the fundamental properties of a novel material.We report here the precision band mapping of a 2-dimensional(2D) spin-orbit(SO) coupling in an optical lattice.By applying the microwave spin-injection spectroscopy, the band structure and spin-polarization distribution are achieved simultaneously.The band topology is also addressed with observing the band gap close and re-open at the Dirac points.Furthermore, the lattice depth and the Raman coupling strength are precisely calibrated with relative errors in the order of 10^(-3).Our approach could also be applied for exploring the exotic topological phases with even higher dimensional system.