Professor Daniele Fausti

University of Trieste and Elettra - Sincrotrone Trieste S.c.p.a., Trieste, Italy

Controlling the properties of complex materials with light

The rich phase diagrams of many transition metal oxides (TMOs) is the result of the intricate interplay between electrons, phonons, and magnons. This makes TMOs very susceptible to external parameters such as pressure, doping, magnetic field, and temperature which in turn can be used to finely tune their properties. The same susceptibility makes TMOs the ideal playground to design experiments where the interaction between tailored electromagnetic fields and matter can trigger the formation of new, sometimes exotic, physical properties. This aspect has been explored in time domain studies [1] and has led to the demonstration that ultrashort mid-IR light pulses can "force" the formation of quantum coherent states in matter, disclosing a new regime of physics where thermodynamic limits may be bridged and quantum effects can, in principle, appear at ambient temperatures.

In this presentation, I will review our recent results in archetypal strongly correlated cuprate superconductors [2,3,4], which demonstrated the feasibility of a light-based control of quantum phases in real materials. I will then introduce our new spectroscopic approach that goes beyond mean photon number observables [5,6,7,8] and show that the statistical features of light can provide richer information than standard linear and non-linear optical spectroscopies. Finally, I will elaborate on our current research direction on leveraging both the electromagnetic field fluctuations and the strong driving of materials to control the onset of quantum coherent states in complex materials.

Selected Publications

[1] Advances in physics 65, 58-238, 2016

[2] Science 331, 189-191 (2011)

[3] Phys. Rev. Lett. 122, 067002 (2019)

[4] https://arxiv.org/abs/2003.13447 (accepted Nat. Phys. 2020)

[5] Phys. Rev. Lett. 119, 187403 (2017)

[6] New J. Phys. 16 043004 (2014)

[7] Nat. Comm. 6, 10249 (2015)

[8] PNAS March 19, 116 (12) 5383-5386 (2019)

After the graduation at the Catholic University of Brescia in 2002 I obtained a doctorate from the from Zernike Institute for Advanced Materials at the University of Groningen in 2008. For the following years I shared my time between the condensed matter division of the Max Plank Group for Structural Dynamics in Hamburg and the Clarendon laboratories in the Physics Department at Oxford University. Currently I run an independent research program at the Physics Department of the University of Trieste and the Syncrotron facility Elettra Sincrotrone S.C.P.A. in Trieste. The aim of my research is to study and control non-equilibrium quantum matter phases by the resonant excitation of low energy degrees of freedom in matter. In particular, I lead a scientific program aiming at combining standard non-equilibrium approaches to a full quantum state reconstruction of light pulses to go beyond mean photon number observables and provide richer statistical information than standard linear and non-linear optical spectroscopies.