Correlated quantum magnetism investigated by experiments under extreme conditions

Abstract

The present Research Internship Abroad (BEPE FAPESP) project aims to realize and learn state-of-the-art experimental methods under simultaneous extreme conditions (ultra low-temperatures TThe present Research Internship Abroad (BEPE FAPESP) project aims to realize and learn state-of-the-art experimental methods under simultaneous extreme conditions (ultra low-temperatures T, high pressures p, and high magnetic fields B) in European high-performance laboratories: the Laboratory for Quantum Magnetism of École Polytechnique Fédérale de Lausanne (LQM-EPFL) and the ISIS facility, Rutherford Appleton Laboratory (ISIS-RAL). With the use of laboratory infrastructure in these European labs, which is not yet available in Brazil, the Intern expects to uncover further insights into the nature of the quantum phase transition and its concomitant emergent quantum states in frustrated two-dimensional spin compound SrCu2(BO3)2, as well as to understand which low-lying interactions account for hard magnetism in the Sm$_x$Y$_{1-x}$Co$_5$ system. These subjects of research are the cornerstone of the current Ph.D. thesis of the BEPE-FAPESP applicant (see FAPESP process number 2019/24711-0).The Intern will also profit from learning new experimental methods in state-of-the-art laboratory infrastructure. In the LQM-EPFL headed by Prof. Henrik Ronnow, the Intern will learn to develop home-built a.c. magnetic susceptibility experiments constructing miniature coils to place into high-pressure cells. This new know-how, synergistically working with a.c. specific heat measurements learned in the Laboratory for Quantum Matter under Extreme Conditions at the University of São Paulo (LQMEC-USP) which is headed by the Intern's supervisor, Prof. Julio Larrea, will allow uncovering a new experimental T-p-B phase diagram at extreme conditions in SrCu2(BO3)2: 18