Method of estimating curie temperature distribution in a magnetic recording layer

A method of estimating a Curie temperature distribution of a plurality of magnetic grains contained in a magnetic recording layer, comprising:

• a first step of obtaining a measurement value of a first parameter with the magnetic recording layer used as a measurement subject, the measurement value being obtained for each of different temperatures of the magnetic recording layer by changing the temperature of the magnetic recording layer, the first parameter having such a property that an absolute value of the first parameter for each magnetic grain takes on a minimum value when the temperature of each magnetic grain reaches a predetermined temperature in the process of increasing the temperature of each magnetic grain, wherein the predetermined temperature varies according to the Curie temperature of each magnetic grain in such a manner as to increase as the Curie temperature increases, and to decrease as the Curie temperature decreases;
• a second step of obtaining a measurement value of a second parameter with the magnetic recording layer used as the measurement subject, the measurement value being obtained for each of different temperatures of the magnetic recording layer by changing the temperature of the magnetic recording layer, the second parameter being related to a value obtained by dividing a standard deviation of a coervicity distribution of the plurality of magnetic grains by the coervicity of the magnetic recording layer;
• and
• a third step of calculating a value related to the Curie temperature distribution of the plurality of magnetic grains based on a first temperature and a second temperature, the first temperature being the lowest temperature at which the absolute value of the measurement value of the first parameter takes on a minimum value, the second temperature being the temperature of the magnetic recording layer at which the value obtained by dividing the standard deviation of the coervicity distribution of the plurality of magnetic grains by the coervicity of the magnetic recording layer takes on a maximum value, the second temperature being obtained from the measurement value of the second parameter.