Pyroelectric detection of ferroelectric polarization in magnetic thin films

摘要

We review the performance of the pyroelectric measurement method in the context of polar states in multiferroic materials in which ferroelectricity coexists with ferromagnetism. The unique point of pyroelectric measurement is the ability to determine the presence of dielectric polarization without having to apply a bias voltage during the measurement. The convenience of the zero-bias technique is illustrated by summarizing experiments on measuring the pyroelectric hysteresis loops of leaky ferroelectric BaTiO3 and PbTiO3 thin film capacitors. This technique was also employed for detecting a polar state in magnetic materials, proving that the electronic polarization in ferrimagnetic Fe3O4 appears at the Verwey transition temperature at 120K and to discover A-site-driven ferroelectricity in epitaxially strained ferromagnetic La2NiMnO6 films. (c) 2018 The Japan Society of Applied Physics.