简介：摘要

         Problems in temporal evolution of symmetry breaking phase
transitions span subjects from high energy and cosmology, to condensed
matter. The reported new approach [1] is the optical study of a
far-from-equilibrium evolution of the electronic charge ordering after a
quench caused by an intense laser pulse. Technique of multi-pulse
spectroscopy with a femto-second resolution allowed to simultaneously
monitor both bosonic and fermionic components, coherent aperiodic
undulations of the order parameter, critical slowing down of the collective
mode (akin to the Higgs boson), and evolution of the particle-hole gap which
is due to the Peierls-BCS mechanism. The numerical modeling with no fitting
parameters allowed reproducing the observations, particularly the
spatio-temporal distortions: “Higgs waves” arising from “earthquakes” -
annihilation events of topological defects in depth of the sample. The
results give a rare access to the in-situ dynamics of phase transitions in
electronic systems. We shall discuss also other manifestation of strong
amplitude perturbations. At a local microscopic scale accessed by the STM,
the amplitude solitons play a role of neutral spin carriers - spinons. Their
aggregation into solitonic lattices gives rise to modulated phases in
spin-polarised superconductors or Charge Density Waves.

In collaboration with D. Mihailovic group at the Jozef Stefan
Institute,Ljubljana, Slovenia.

[1] R. Yusupov, et al, “Coherent dynamics of macroscopic electronic order
through a symmetry breaking transition”, Nature Physics, 2010.