Cryogen-free variable temperature scanning SQUID microscope

被引：13

作者：

Bishop-Van Horn, Logan ^{[1
,2
]}

Cui, Zheng ^{[1
,3
]}

Kirtley, John R. ^{[4
]}

Moler, Kathryn A. ^{[1
,3
,4
]}

机构：

[1] Stanford Inst Mat & Energy Sci, SLAC Natl Accelerator Lab, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA

[2] Stanford Univ, Dept Phys, Stanford, CA 94305 USA

[3] Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA

[4] Stanford Univ, Geballe Lab Adv Mat, Stanford, CA 94305 USA

来源：

REVIEW OF SCIENTIFIC INSTRUMENTS | 2019年 / 90卷 / 06期

关键词：

SUPERCONDUCTIVITY;

D O I：

10.1063/1.5085008

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

Scanning Superconducting QUantum Interference Device (SQUID) microscopy is a powerful tool for imaging local magnetic properties of materials and devices, but it requires a low-vibration cryogenic environment, traditionally achieved by thermal contact with a bath of liquid helium or the mixing chamber of a wet dilution refrigerator. We mount a SQUID microscope on the 3 K plate of a Bluefors cryocooler and characterize its vibration spectrum by measuring SQUID noise in a region of sharp flux gradient. By implementing passive vibration isolation, we reduce relative sensor-sample vibrations to 20 nm in-plane and 15 nm out-of-plane. A variable-temperature sample stage that is thermally isolated from the SQUID sensor enables the measurement at sample temperatures from 2.8 K to 110 K. We demonstrate these advances by imaging inhomogeneous diamagnetic susceptibility and vortex pinning in optimally doped yttrium barium copper oxide above 90 K.

引用

页数：7