Chirality and Topology in DNA-type Chiral Materials
Department of condensed matter physics, Weizmann Institute of Science, Israel
Abstract: In physics, chirality usually refers to the locking of spin and momentum, such as in Weyl fermions and circularly-polarized light. In chemistry and biochemistry, however, it is the geometric asymmetry of non-superposable left or right-handed mirror images that constitutes chirality. While seemingly unrelated characters in different fields, the chiral geometry can lead to topological electronic properties in chiral molecules or solids, as we recently discovered in theory and experiments. This electronic topology is encoded in the orbital nature of the wave function, with an orbital-momentum locking occurring. This orbital-momentum locking enables the chiral molecule to polarize the quantum orbital and induces spin polarization when spin–orbit coupling is present. Moreover, the chiral orbital effect can cause anomalous circularly-polarized light emission in organic LEDs. Our work reveals the intriguing information transfer between atomic structure, electronic orbital/spin, and light handedness, and provides a path to manipulate spin and light-matter interaction through chiral structure engineering.
Host: Shulei Zhang