Nanowerk October 23, 2020
Topological insulators do not conduct electricity in their bulk but channel it along their surface through edge modes. The edge modes can be destroyed only through the use of force. This topological property makes such materials promising candidates in future quantum devices when combined with Floquet engineering. An international team of researchers (USA – SLAC National Accelerator Laboratory, Stanford University, The Flatiron Institute, Spain, Germany, Switzerland) has demonstrated that short corkscrew laser flashes can be used to track these short-lived states. In their earlier work the researchers had demonstrated how to make use of circular dichroism to detect equilibrium topology. Now in computer simulations they have demonstrated that even without the precise knowledge of the energy, the difference of the signal between left- and right-handed light is sufficient to tell us which state the electrons are in. The scientists now plan to use their simulations to predict states of matter which have not even been theorized yet…read more. Open Access TECHNICAL ARTICLE
…With a second laser flash of either left- or right-handed polarization (LCP/RCP) and a short time difference, researchers can eject electrons from the sample and detect their short-lived topology. Credit: Michael Schüler, Stanford Institute for Materials and Energy Sciences