Dr. Richard Averitt (UC San Diego)
The past decade has seen enormous advances in materials and ultrafast optical spectroscopy spanning from classical to quantum physics. On the classical front, metamaterials are artificial composites with unique electromagnetic properties that derive from their sub-wavelength structure. Metamaterials enable new ways to control light with negative refractive index and cloaking as two examples of considerable interest. Moving to the quantum realm, correlated electron materials exhibit fascinating phenomena ranging from superconductivity to metal-insulator transitions. Many of these materials exhibit colossal changes to small perturbations, which includes electromagnetic excitation. This opens up exciting possibilities such as photoinduced phase transitions with the goal to create metastable states with unique properties. Following an introduction to this research field, I will show examples of our work using picosecond terahertz pulses to probe and control matter. This includes our recent demonstration of a metamaterial enhanced electric field initiated insulator-to-metal transition in vanadium dioxide and using optical excitation to create a metastable ferromagnetic metallic state in insulating manganite thin films.
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