The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A velocity field approach is proposed to characterize the topological invariants of quantum states based on the Poincar–Hopf theorem. It is found that the zero modes of the velocity field flow play the roles of effective topological charges to dominate the topological invariants against the parameter deformation. The validity of this approach is demonstrated by using the quantum sphere and torus models...
A geometric criterion of the topological phase transition for non‐Hermitian systems is proposed, based on the length of the boundary of the bulk band in the complex energy plane for non‐Hermitian systems. For 1D systems, it is found that the topological phase transition occurs when the derivatives of the length with respect to parameters are discontinuous. For 2D systems, when the length is discontinuous,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.