Only one of several invited lectures is presented. Members of project group have presented achievements as invited speakers at several international conferences: International Conference of the series on Stripes and High Tc Superconductivity STRIPES 2011 in Rome, The 26th International Conference on Low Temperature Physics in Beijing, International Conference on Photoinduced Phase Transitions and Cooperative Phenomena PIPT4 in Poland, International Research School and Workshop on Electronic Crystals ECRYS 2011 in France ect.
B.04 Guest lecture
COBISS.SI-ID: 24923431Following the recent surge in interest in ultrafast studies of superconductors and related materials, and particularly a flurry of activity in quantum mechanical theory of nonequilibrium phenomena we organised a short and focused adhoc 3day meeting. The scope of the meeting was to focus on new approaches to theory of ultrafast phenomena in cuprates and related systems, including fundamental problems of hot carrier relaxation in strange metals, collective phenomena and single particle relaxation. We were able to bring together two national and three foreign groups from Germany and Italy.
B.01 Organiser of a scientific meeting
COBISS.SI-ID: 26372647Abstract of the Invited talk presents evidence for pair formation and phase coherence occuring in sequence
B.04 Guest lecture
COBISS.SI-ID: 26783527With our new experimental method we can achieve realtime high resolution investigations of the critical system trajectories through symmetrybreaking transitions in different complex systems which belong to a number of different universality classes and include the study of nontrivial transitions to newly discovered hidden states of matter. We investigate coherent collective field oscillations and the fundamentals of topological defect creation by the KibbleZurek mechanism including a study of their annihilation in the aftermath of symmetrybreaking transitions. We aim to control the coherent trajectories at bifurcation points by laser pulses and external fields. Transition trajectories to and from hidden states are of particular interest for practical applications in new femtosecond state change memory devices.
B.04 Guest lecture
COBISS.SI-ID: 26664487Ultrashort laser pulses are a convenient tool for coherent excitation of phonons and collective electroniclattice modes in CDW systems. Due to the availability of strong laser pulses the phonons can be driven far from equilibrium, exposing nonlinear effects. These effects are often difficult to track by the standard pumpprobe optical spectroscopy due to the presence of large firstorder signals. Trying to overcome this problem we devised a differential multipumppulse technique that enables us to detect small differences between highly excited trajectories of a system. Using this technique we were able to investigate a hitherto unexplored aspect of the CDW amplitude mode behavior under strongly driven nonequilibrium conditions. By means of this approach we are able to directly investigate the anharmonicity of the effective AM potential, as well as detect the anharmonic coupling of the collective bosonic mode (the AM) of the CDW to other lattice modes in 1TTaS2 and TbTe3. Apart from the coherent response we use the same technique to study the incoherent recombination of topological defects after a quench of the system by an intense laser pulse. The evolution of the AM is found to follow a slower recovery due to incoherent annihilation of the topological defects on a timescale up to ~30 ps and is fairly consistent with the thermal diffusion on longer timescales.
B.04 Guest lecture
COBISS.SI-ID: 26132263