Katedra fyziky kondenzovaných látek

We have a pleasure to invite you to attend the joint seminar
of the Department of Condensed Matter Physics (DCMP)
and the Materials Growth and Measurement Laboratory (MGML) http://mgml.eu.

Program

Magnetocaloric effect measurement in pulsed magnetic fields; applications to solid oxygen and frustrated magnets

lecture given by:

Toshihiro Nomura

HLD-EMFL, Helmholtz-Zentrum Dresden-Rossendorf

The seminar takes place in the lecture room F2 
of the Faculty of Mathematics and Physics, Ke Karlovu 5, Praha 2
on Wednesday, 13.2. 2019 from 14:10 

Vladimír Sechovský
On behalf of the DCMP and MGML

Abstract 

When a material is magnetized or demagnetized under adiabatic conditions, its temperature changes to conserve the total entropy. This is called the magnetocaloric effect (MCE). In pulsed magnetic fields, the MCE is easily observed due to the short duration of time. Recently, the MCE measurement in pulsed magnetic fields was established and applied to various magnetic materials. The MCE measurement serves as an ideal technique to (i) reveal the magnetic-field-temperature phase diagram, (ii) obtain the entropy information, and (iii) discuss Grüneisen parameter which reflects the quantum criticality.

In this talk, I present some examples of the MCE researches in pulsed magnetic fields up to 60 T. The examples will include solid oxygen and frustrated magnets (Sr₃Cr₂O₈, MnCr₂S₄, BaCo₂V₂O₈).

[1] T. Kihara et al., Rev. Sci. Instrum. 84, 074901 (2013).

[2] T. Nomura et al., Phys. Rev. B 95, 104420 (2017).

[3] Z. Wang et al, Phys. Rev. Lett. 120, 207205 (2018).

FIG. Adiabatic temperature change of solid oxygen along the b-γ phase boundary.