Zavjalov V V, Savin A M, Hakonen P J
Low Temperature Laboratory, Department of Applied Physics, Aalto University, PO Box 15100, 00076 Aalto, Finland.
J Low Temp Phys. 2019;195(1):72-80. doi: 10.1007/s10909-018-02130-1. Epub 2018 Dec 17.
We have designed and characterized a cryogenic amplifier for use in He NMR spectrometry. The amplifier, with a power consumption of mW, works at temperatures down to 4 K. It has a high-impedance input for measuring a signal from NMR resonant circuit, and a 50 differential input which can be used for pick-up compensation and gain calibration. At 4.2 K, the amplifier has a voltage gain of 45, output resistance 146 and a 4.4 MHz bandwidth starting from DC. At 1 MHz, the voltage and current noise amount to 1.3 and 12 , respectively, which yields an optimal source impedance of k .
我们设计并表征了一种用于氦核磁共振光谱仪的低温放大器。该放大器功耗为 毫瓦，可在低至4K的温度下工作。它具有用于测量来自核磁共振谐振电路信号的高阻抗输入，以及一个50 差分输入，可用于拾取补偿和增益校准。在4.2K时，该放大器的电压增益为45，输出电阻为146 ，从直流开始的带宽为4.4MHz。在1MHz时，电压噪声和电流噪声分别为1.3 和12 ，这产生了 千欧的最佳源阻抗。
