标题： 通过隧穿电流偏转传感的力-噪声光谱学 显示英文标题

标题： Force-noise spectroscopy by tunnelling current deflection sensing

摘要： 用于低温隧道显微镜中交流力测量的机电装置已被开发，该装置能够实现极高的力分辨率。 将振动的串扰用于测量隧道电流，以检测力感应悬臂梁的偏转。 我们展示了其在使用多晶铱材料的隧道接触中测量力噪声的能力。 根据温度、弹簧常数和电流，可能达到$\rm {fN}/\sqrt{\rm Hz}$范围内的分辨率。 我们在预期声子最大态密度的能量处观察到力噪声的峰值水平，这表明非弹性输运过程对力波动有贡献。 显示英文摘要

摘要： An electro-mechanical setup for the measurement of AC-forces in a low-temperature tunnelling microscope has been developed, which enables extremely high force resolution. The crosstalk of vibrations onto the tunnelling current is used to measure the deflection of a force-sensing cantilever beam. We demonstrate its capability to measure the noise of the force at a tunnelling contact using polycrystalline Iridium. Depending on temperature, spring constant and current, a resolution in the range of $\rm {fN}/\sqrt{\rm Hz}$ is possible. We observe peak levels of the force-noise at the energy of the expected phonon maximal density of states, which suggests that inelastic transport processes contribute to force fluctuations.