Novel States of Quantum Matter at Extreme Conditions
In this talk, I will discuss the state of the-art of novel states of quantum matter underpinned by experimental methods under extreme conditions: very low temperatures, very high-pressures and high magnetic fields.
I focus my discussion on the physics of quantum phase transition (QPT), the transition that separates two different states at zero temperature (T= 0K). Electronic and spin interaction in materials as heavy fermion Ce3Pd20Si6 and frustrated magnet SrCu2(BO3)2 can be modified by the application of high-pressure and high magnetic fields. By measuring challenge specific heat, magnetic susceptibility and electrical transport at extreme conditions, we observe unconventional physical properties as fingerprint of the existence of a QPT and concomitant novel state of quantum matter, such as Non-Fermi liquid and plaquette phases. I will discuss some physical scenarios that tentatively account for the physics of a quantum phase transition, including those ascribed to low-lying interactions between dipolar and quadrupolar electronic degree of freedoms [1-2].
Finally, I will present ongoing projects involved the investigation of strongly correlated electron systems as potential material candidates for thermoelectric applications [3-4].
 M. E. Zayed, J. Larrea J, et al. Nature Physics 13, 962 (2017);
 J. Larrea J., et al . Phy. Rev. B 93, 125121 (2016); V. Martelli, J.Larrea J., et. al, submitted to Science Advances Ref: Ms. No. aax8425;
 V. Martelli, J. Larrea J., et al . Phys. Rev. Lett. 120, 125901 (2018) (Editor Suggestion);
 J. Munevar, J. Larrea J. et al, Phys. Rev. B 95, 125138 (2017).
Prof. Dr. Larrea will give this talk via video conference as Visitor Professor in the group of Prof. Chihiro Sekine at Muroran Institute of Technology (Japan). His visit launches the collaboration program supported financially by grant AUCANI USP-Santander: “Novos Docentes Novas Parcerias Internacionais”.