论文标题
能够在MK温度和矢量磁场上进行电子自旋共振和泵探针光谱的扫描隧道显微镜
A scanning tunneling microscope capable of electron spin resonance and pump-probe spectroscopy at mK temperature and in vector magnetic field
论文作者
论文摘要
在过去的十年中，通过将电子自旋共振（ESR）或泵探针光谱与扫描隧道显微镜（STM）等技术相结合，从而实现了原子量表的旋转动力学。在这里，我们展示了Millikelvin（MK）的超高真空（UHV）STM操作，以及能够具有ESR和泵探针光谱的矢量磁场。通过实施GHz兼容的电缆，我们在保持MK碱温度的同时，在连接处实现了可观的RF振幅。我们通过在MGO/AG（100）上使用两个实验ESR模式（频率扫描和磁场扫描）并提取有效的G因子，从而证明了设置的成功操作。我们将ESR转换向MHz追踪到由MK碱温度启用的前所未有的低频带。我们还基于适合研究动力学至纳秒范围的波形测序的全电动泵探针方案。我们通过检测MGO/AG（100）的单个Fe原子的自旋松弛时间T1进行基准测试，并注意野外强度和方向依赖于松弛时间。
In the last decade, detecting spin dynamics at the atomic scale has been enabled by combining techniques like electron spin resonance (ESR) or pump-probe spectroscopy with scanning tunneling microscopy (STM). Here, we demonstrate an ultra-high vacuum (UHV) STM operational at milliKelvin (mK) and in a vector magnetic field capable of both ESR and pump-probe spectroscopy. By implementing GHz compatible cabling, we achieve appreciable RF amplitudes at the junction while maintaining mK base temperature. We demonstrate the successful operation of our setup by utilizing two experimental ESR modes (frequency sweep and magnetic field sweep) on an individual TiH molecule on MgO/Ag(100) and extract the effective g-factor. We trace the ESR transitions down to MHz into an unprecedented low frequency band enabled by the mK base temperature. We also implement an all-electrical pump-probe scheme based on waveform sequencing suited for studying dynamics down to the nanoseconds range. We benchmark our system by detecting the spin relaxation time T1 of individual Fe atoms on MgO/Ag(100) and note a field strength and orientation dependent relaxation time.
