Low-temperature magnetic orientation noise in a colossal magnetoresistive film

Discrete two-state resistance fluctuations are found deep within the metallic phase of a colossal-magnetoresistive film. Thermodynamic derivatives show the ratios of entropy changes to magnetic moment changes of these fluctuators to be very small, with mixed signs, unlike fluctuators found near the transition temperature. These low ratios are a signature of magnetic orientation fluctuations, indicating an important role for domain-wall effects on the transport properties in the metallic regime.