发展了一种超灵敏技术,对铁氧体材料的小球样品能够测量微波磁化率分量小到10~(-5)的数量级。这种方法的特点是采用反馈线路将信号速调管锁定在含有样品的高Q园柱腔的3dB点上。通过信号速调管对晶体振盪器稳频的参考速调管拍频,测量腔体在半功率点处的频宽的误差能小于几百赫兹,从而获得非常准确的结果。迄今为止,这种技术最重要的应用是取远离铁磁谐振几千奥斯特的有效线宽的形式来研究微波弛豫的现象。 An ultrasensitive technique has been developed to measure microwave susceptibility components as small as 10-5 on ferritic pellets. This method features a feedback line that locks the klystron tube at the 3dB point of the high Q-plenum containing the sample. By tuning the frequency of the klystron to a crystal oscillator frequency-stabilized reference tone tube, the error in the bandwidth of the measurement cavity at the half-power point can be less than several hundred hertz, resulting in very accurate results. To date, the most important application of this technique has been to study the phenomenon of microwave relaxation in the form of an effective linewidth away from the ferromagnetic resonance of tens of oersteds.