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The study of spin dynamics in semiconductors was the first research field of the group, starting with the first observation of optical pumping (i.e. optical injection of spin polarized electrons using circularly polarized photons) in a solid. This phenomenon was demonstrated indirectly in silicon via a nuclear magnetic resonance technique.
Electrons in semiconductors are often treated as classical particles, but this is not possible when their volume density exceeds a critical value called the effective density of states. Above this density the semiconductors becomes degenerate and the electrons must be treated as Fermions. Via the Paul principle, this quantum nature of the electrons has a profound effect on spin transport.
Currently, one of the main research topics in condensed matter physics deals with the electronic properties of ultrathin compounds for which the scientific community has consecrated a significant effort since the discovery of graphene in 2004. This young field experienced a big boost recently thanks to the isolation of atomically thin semiconductors based on transition metal dichalcogenides (TMD), such as MoS2 and WSe2. The direct bandgap of monolayers and their efficient coupling with light makes them versatile and promising fundamental bricks for future nanoelectronics and optoelectronic devices.
The intimate relationship between chirality and electron spin magnetism is an emerging field based on the action of chiral objects (molecules, surfaces states) as a spin filter for electron transport. By analogy with differential absorption of polarized light by chiral molecules, spin polarized electrons which are de facto chiral objects, can interact with chiral molecules by setting off a spin dependent scattering asymmetry.
New spintronic devices are based on the different timescale at which electrons, spins and lattice interacts. This field was opened by the availability of the first femtosecond laser pulses. Solid state physics could expand in a new dimension where the electronic excitations can be induced in non-equilibrium conditions non accessible by simply increasing temperature.
