Chiral Supramolecular Structures as Spin Filters

Abstract

We describe a newly discovered effect, termed chiral induced spin selectivity (CISS), which offers promise for the use of organic materials to manipulate electron spins. CISS has been reported for electron transmission and conduction through organic molecules. In particular, the electron transport through chiral molecules is spin selective, and the consequent spin polarization is very large as compared to inorganic spin filters. This phenomenon is unanticipated, as organic molecules are known for their small spin–orbit coupling (SOC) and the molecules used are not magnetic. Results are presented in which spin polarization was measured for photoelectrons and for bound electrons transmitted through various chiral molecules. In addition a CISS based memory device is presented, demonstrating the new horizons opened by this effect.