Generation of giant single-cycle pulses of THz light for controlling matter

by Dr Vitaliy Goryashko (Uppsala University)

Thursday 7 Apr 2016, 15:15 → 16:00 Europe/Stockholm

Å12167

THz pulses are an excellent fine stimulus for studying low-energy collective excitations in strongly-correlated multi-atomic systems. Such excitations with their spectra in the THz range comprise of ‘breathing dynamics’ of DNA helices, spins waves in antiferromagnets, Josephson waves in superconductors, phonons of crystal lattices and structural transformations in the bacteriorhodopsin, which is one of the two light-harvesting proteins responsible for life on Earth. The crucial progress in this emerging field of research has been made after 2007 thanks to the development of strong-field laser-based THz sources. Further progress and engineering of new highly non-equilibrium states of matter call for a THz light source greatly extending the capabilities of the existing ones. In the talk I will give a brief overview of controlling matter with THz light such as light-induced superconductivity and present a novel concept of generation of quasi-half-cycle THz pulses with a field strength in the Volt/Ångström range (/inter-atomic fields/) and with variable polarization. The concept is based on using the coherent spontaneous radiation from pre-bunched electron beams and controlling the slippage between electrons and the radiation field. It is the analog of the mode locking in conventional lasers.

Slides Vitaliy_Single_cycle_THz_2016.pdf