Materials with macroscopic orders resulting from quantum degrees of freedom are of fundamental interest and are widely used in sensors, memory devices and other applications. That makes crystalline ferroic materials an ideal “fruit fly” to test the ultrafast optical manipulation on. In particular, manipulation of their quantum states and associated dynamics are at the heart of many prospective applications, as in information storage and spintronics, light-emitting diodes or photovoltaics. Recent advent of femtosecond lasers and large-scale spectroscopy facilities enabled ultrafast experiments on a natural electronic timescale. This interdisciplinary workshop will bring together physicists, chemists and materials scientists to improve the simulation methodology for computing photoexcited dynamics in quantum materials. The proposed workshop is split into 3 sessions, which will (1) identify the classes of ferroic materials most suitable for ultrafast manipulation, (2) discuss photophysics of halide perovskite materials for optoelectronics, (3) address simulation methodologies for excited state dynamics and optical control.
In recent years optically-induced phase transitions [1-3], excitation of coherent phonons [7-10], switching of ferroelectric polarization [4-5] and optically enhanced superconductivity [6] were demonstrated. Existing computational methodologies include TDDFT, TD-GW+DMFT, surface hopping, Ehrenfest, hierarchy equations of motion. The workshop will target the development of efficient simulation protocols, adequate for modeling photoinduced switching of order parameters and the operation of halide perovskite-based LEDs and photovoltaics. Ample time for discussions will be allocated after every talk to stimulate the exchange of ideas. Each session will conclude with a brainstorming session of 30 min.

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