Nanofizika - Nanophysics
Spin dynamics and transport at the quantum edge in low dimensional nanomaterials
Principal Investigator (PI): Dr. Ferenc Simon
Duration in months: 60
Starting: 2010. november
Funding: 1 230 000 Euró
Sustainable development in information technology calls for an ever increasing information processing and storage capability. A promising route to maintain exponential growth capability, i.e. to keep on the Moore's roadmap, is to turn to the electron spins as information carriers rather than their charge. This field, spintronics, has enormous potential whose exploitation requires solid knowledge in the fundamentals of spin dynamics and spin transport.
Herein, novel nanomaterials are suggested for spintronics purposes, such as graphene and single-wall carbon nanotubes (SWCNTs). These, fundamental two- and one-dimensional carbon allotropes are promising candidates for such purposes, carbon being a light element with a low spinorbit coupling which results in a long spin coherence. There are several fundamental open issues, e.g. the dominant spin orbit coupling mechanism in graphene, whether bulk electron spin resonance can be bserved for this material, and the length of the spin diffusion length. For SWCNTs, the ground state of isolatedmetallic tubes is known to be the Tomonaga-Luttinger liquid (TLL), which greatly limit the spin coherence, but it is at present open whether this state is destroyed when an ensemble of interacting metallic tubes is studied. The decay time and spin symmetry of optical excitations (excitons) in semiconducting SWCNTs is yet unknown.
Our goal is to pursue electron spin resonance in graphene and carbon nanotubes and to perform optically detected magnetic resonance in carbon nanotubes. We will commission a magnetoptical spectrometer with a substantial added value.
The expected results are characterization of spin transport capabilities of these materials and understanding of the spin decoherence mechanisms. The PI leads magnetic resonance studies of these materials, shown by his more than 300 citations to this field (the total being over 470) and his 15 Physical Review Letters papers in this field (of which for 9 he is main Author).