New Physics in Driven Quantum Materials by Andrea Cavalleri
I will discuss how coherent electromagnetic radiation at Tera-Hertz and mid-infrared frequencies can be used to drive complex solids. Collective excitations are driven nonlinearly, leading to coupling amongst otherwise virtually non-interacting normal modes of the material. Driving gives rise to non-thermal states with unconventional properties, and sometimes with emergent order. Interesting examples involve the nonlinear control of the crystal lattice, used to induce magnetic order, ferroelectricity and non-equilibrium superconductivity at high temperatures.
About the Speaker:
Andrea Cavalleri is the founding director of the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg (Germany) and a professor of Physics at the University of Oxford (UK). After receiving a laurea degree from the University of Pavia (Italy), he held graduate, postgraduate, and research staff positions at the University of Essen (Germany), at the University of California, San Diego (US), and at the Lawrence Berkeley National Laboratory (US). He joined the Oxford faculty in 2005.He is best known for his experimental studies of the photoinduced phase transition in materials with strongly correlated electrons, such as transition metal oxides and organic conductors. In recent years, his research group has developed techniques that make use of strong TeraHertz pulses to manipulate directly lattice distortions and other collective modes of solids. Through precise optical control, he has shown that ordered states like superconductivity or ferroelectricity can be induced by light at temperatures far above the thermodynamic transition temperature. Motivated by the need to probe-driven materials, he has also been a major driver in the development of ultrafast X-ray techniques since their inception in the late 1990s through their modern incarnation at X-ray Free Electron Lasers. Cavalleri is a recipient of the 2004 European Science Foundation Young Investigator Award, of the 2015 Max Born Medal from the IoP and the DFG, of the 2015 Dannie Heineman Prize from the Academy of Sciences in Goettingen and of the 2018 Isakson Prize from the American Physical Society. He is a fellow of the APS, of the AAAS, and of the IoP. In 2017, he was elected Member of the Academia Europaea.
Practical information
This year, the Physics Colloquium has a new format:
- Onsite at Campus Limpertsberg, where you will have the opportunity to meet the speaker over lunch. The catering is offered only to the registered participants from noon in the BSC Hall, therefore kindly register as soon as possible on 6 March the latest.
- Online – through Webex – to allow you to listen to the talk in case you are travelling or cannot make it on-site at Campus Limpertsberg. Credentials: Meeting number (access code): 2788 641 9612; Meeting password: a43cSm7mRew.