Ultrafast evolution and transient phases of a prototype out-of-equilibrium Mott-Hubbard material.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28067228.
- Also identified by DOI 10.1038/ncomms13917 and PMC identifier 5228036.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The study of photoexcited strongly correlated materials is attracting growing interest since their rich phase diagram often translates into an equally rich out-of-equilibrium behaviour. With femtosecond optical pulses, electronic and lattice degrees of freedom can be transiently decoupled, giving the opportunity of stabilizing new states inaccessible by quasi-adiabatic pathways. Here we show that the prototype Mott-Hubbard material V<sub>2</sub>O<sub>3</sub> presents a transient non-thermal phase developing immediately after ultrafast photoexcitation and lasting few picoseconds. For both the insulating and the metallic phase, the formation of the transient configuration is triggered by the excitation of electrons into the bonding a<sub>1g</sub> orbital, and is then stabilized by a lattice distortion characterized by a hardening of the A<sub>1g</sub> coherent phonon, in stark contrast with the softening observed upon heating. Our results show the importance of selective electron-lattice interplay for the ultrafast control of material parameters, and are relevant for the optical manipulation of strongly correlated systems.