We present a stability investigation of the Stockholm laboratory cryo soft x-ray microscope. The microscope operates at a wavelength of 2.48 nm and can image biological samples at liquid-nitrogen temperatures in order to mitigate radiation damage. We measured the stability of the two most critical components, sample holder and optics holder, in vacuo and at cryo temperatures at both short and long time scales with a fiber interferometer. Results revealed vibrations in the kHz range, originating mainly from a turbo pump, as well as long term drifts in connection with temperature fluctuations. With improvements in the microscope, earlier stability issues vanished and close-to diffraction-limited imaging could be achieved. Moreover, our investigation shows that fiber interferometers are a powerful tool in order to investigate position-sensitive setups at the nanometer level.

中文翻译：

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用光纤干涉法研究低温软 X 射线显微镜的稳定性

我们介绍了斯德哥尔摩实验室低温软 X 射线显微镜的稳定性研究。显微镜的工作波长为 2.48 nm，可以在液氮温度下对生物样本进行成像，以减轻辐射损伤。我们使用光纤干涉仪在真空和低温条件下，在短时间和长时间范围内测量了两个最关键的组件（样品支架和光学支架）的稳定性。结果显示 kHz 范围内的振动主要来自涡轮泵，以及与温度波动相关的长期漂移。随着显微镜的改进，早期的稳定性问题消失了，并且可以实现接近衍射极限的成像。而且，