| 摘要 |
<p>PROBLEM TO BE SOLVED: To allow measurement of an AC magnetic field generated from a sample by an instrument which measures the AC magnetic field by using an oscillating probe, even in the case where the sample generates the AC magnetic field having such a high frequency that an effective spring constant of the prove is not varied.SOLUTION: An AC magnetic field having a high angular frequencyωis given from a sample 2 to a probe 111 excited at an excitation frequencyω, and simultaneously, an AC magnetic field including one or more angular frequency components (for example,ω-ω) slightly different from the angular frequencyωis given by an AC magnetic field generator 132. Because of magnetic interaction between the AC magnetic field (modulation AC magnetic field) and probe magnetization, oscillation of the angular frequencyωof the probe 111 is modulated by a modulation angular frequencyωto vary an effective spring constant of the probe when the AC magnetic field having the angular frequencyω-ωis given. Oscillation of the probe 111 is detected by a signal extractor 14, and a modulated signal generated in excited oscillation is extracted from the detection signal. An AC magnetic field response of the sample 111 is measured by an AC magnetic field response measurement instrument 15 on the basis of the extracted signal.</p> |
