A scanning superconducting quantum interference device microscope with high spatial resolution for room temperature samples
A scanning superconducting quantum interference device microscope with high spatial resolution for room temperature samples
复制标题
一种用于室温样品的高空间分辨率扫描超导量子干涉器件显微镜
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
J. Dechert
中科院分区：
文献类型：
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作者：
Friederike Gruhl;M. Mück;Marc von Kreutzbruck;J. Dechert
We have developed a scanning superconducting quantum interference device (SQUID) microscope based on niobium tunnel junction direct current (dc) SQUIDs. It employs either a SQUID magnetometer or a planar first order gradiometer with an effective area of 40×40 μm2 and a magnetic field resolution on the order of 1 pT/√Hz at frequencies above a few hertz. The gradiometer has a base line of 1 mm. The SQUIDs are mounted inside the insulation vacuum of a fiberglass helium Dewar, and are thermally coupled to the helium bath via a brass block. A sapphire window with a thickness of about 50 μm separates the SQUIDs from the room temperature sample. We have also investigated different window materials, such as tungsten or iridium, and found them equally useful. The stand-off distance between SQUID and room temperature sample can be as low as 75 μm, and the spatial resolution of the microscope is about 50–100 μm. The SQUID sensor is read out using conventional dc SQUID electronics with a bandwidth of 1 kHz and a slew...
