TRR 360 Seminar:

Controlled quantum materials

Daniele Fausti

Controlled quantum materials
D. Fausti ^1,2,3
1 Department of Physics, University of Trieste, Trieste
² Elettra Sincrotrone Trieste S.c.p.a., Trieste
³ Department of Physics, University of Erlangen Nuremberg

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 and demonstrate the feasibility of a light-based control of quantum phases in real materials [2,3,4]. I will then introduce our new approaches to time domain spectroscopy going beyond mean photon number observables [5-10] and show that the statistical features of light can provide information on superconducting fluctuations beyond standard linear and non-linear optical spectroscopies [11]. Finally, I will elaborate on our current research effort to use cavity electrodynamics to control fluctuations in matter and thereby the onset of quantum coherent states in complex materials [12].

References:
[1] Advances in Physics 65, 58-238, 2016
[2] Science 331, 189-191 (2011)
[3] Phys. Rev. Lett. 122, 067002 (2019)
[4] Nature Physics 17, 368–373 (2021)
[5] Phys. Rev. Lett. 119, 187403 (2017)
[6] New J. Phys. 16 ,043004 (2014)
[7] Nat. Commun. 6, 10249 (2015)
[8] PNAS March 19, 116 (12) 5383-5386 (2019)
[9] J. of Physics B 53, 145502 (2019)
[10] Optics Letters 45, 3498 (2020)
[11] Light: Science & Applications 11, # 44 (2022)
[12] Nature 622, 487–492 (2023)