Fieldcooled

Field-cooled refers to a process in materials science and physics where a material is subjected to a magnetic or electric field while being cooled to a low temperature, typically below its transition temperature. This technique is commonly used in the study of magnetic and ferroelectric materials to investigate their behavior under applied fields during cooling.

In magnetic systems, field-cooling involves cooling a sample from above its Curie temperature (for ferromagnetic materials) or Néel temperature (for antiferromagnetic materials) in the presence of an external magnetic field. This method helps distinguish between different magnetic states, such as superparamagnetic or glassy behavior, by preserving induced magnetic alignment as the material cools. The resulting magnetization is often measured during subsequent warming (zero-field-cooled or field-cooled curves), revealing hysteresis effects and phase transitions.

Field-cooling is also applied in ferroelectric materials to study polarization behavior under an electric field during cooling. By applying an electric field while lowering the temperature, researchers can induce and stabilize specific polarization states, useful for characterizing phase transitions and domain structures.

The technique is particularly valuable in investigating systems exhibiting slow dynamics, such as spin glasses or relaxor ferroelectrics, where thermal equilibrium is not easily achieved. Field-cooled measurements provide insights into energy landscapes, frustration effects, and metastable states, complementing other characterization methods like AC susceptibility or calorimetry. Variations in field strength, cooling rate, and sample history allow for systematic exploration of material properties.