论文标题
具有单电子自旋灵敏度的鱿鱼尖端，用于高场和超低温度纳米磁成像
SQUID-on-tip with single-electron spin sensitivity for high-field and ultra-low temperature nanomagnetic imaging
论文作者
论文摘要
扫描纳米级超导量子干扰装置（纳米Quids）对低维系统的磁性，自旋和传输性能的高度敏感定量成像越来越感兴趣。利用专门设计的凹槽石英毛细管将其拉入锋利的移液器中，我们制造了最小的鱿鱼端（SOT）设备，有效直径降至39 nm。将电阻分流的集成在与移液器顶点相近，再加上自我对齐的IN和SN的沉积，导致SOT的通量噪声为42 N $φ_0$ HZ $^{ - 1/2} $，产生创纪录的低旋转噪声，使得创纪录的低旋转噪声为0.29 $μ_b$ Hz $ hz $ hz $^$^{ - 1/2} $。此外，新的SOT在亚克尔文温度和高2.5吨以上的高磁场处的功能。将SOTS整合到扫描探针显微镜中，使我们能够为300 mk的单个Fe $ _3 $ _4 $ _4 $ _4 $ _4 $ _4 $ _4 $ _4 $ _4 $ _4 $ _4纳米型弹簧图像成像。我们的结果表明，简单的磁化轴方向在室温下从（111）方向过渡到平面方向，这可以归因于fe $ _3 $ o $ _4 $的Verwey相变。
Scanning nanoscale superconducting quantum interference devices (nanoSQUIDs) are of growing interest for highly sensitive quantitative imaging of magnetic, spintronic, and transport properties of low-dimensional systems. Utilizing specifically designed grooved quartz capillaries pulled into a sharp pipette, we have fabricated the smallest SQUID-on-tip (SOT) devices with effective diameters down to 39 nm. Integration of a resistive shunt in close proximity to the pipette apex combined with self-aligned deposition of In and Sn, have resulted in SOT with a flux noise of 42 n$Φ_0$Hz$^{-1/2}$, yielding a record low spin noise of 0.29 $μ_B$Hz$^{-1/2}$. In addition, the new SOTs function at sub-Kelvin temperatures and in high magnetic fields of over 2.5 T. Integrating the SOTs into a scanning probe microscope allowed us to image the stray field of a single Fe$_3$O$_4$ nanocube at 300 mK. Our results show that the easy magnetization axis direction undergoes a transition from the (111) direction at room temperature to an in-plane orientation, which could be attributed to the Verwey phase transition in Fe$_3$O$_4$.
