Superfluid helium nanoscope insert with millimeter working range

Naoki Kamiya, Kazuki Kuramoto, Kento Takishima, Tatsuya Yumoto, Haruka Oda, Takeshi Shimi, Hiroshi Kimura, Michio Matsushita, Satoru Fujiyoshi
2022 Review of Scientific Instruments  
A superfluid helium insert was developed for cryogenic microscopy of millimeter-sized specimens. An optical-interferometric position sensor, cryogenic objective mirror, and piezo-driven cryogenic stage were fixed to an insert holder that was immersed in superfluid helium. The single-component design stabilized the three-dimensional position of the sample, with root-mean-square deviations of ( x, lateral) 0.33 nm, ( y, lateral) 0.29 nm, and ( z, axial) 0.25 nm. Because of the millimeter working
more » ... ange of the optical sensor, the working range of the sample under the active stabilization was ( x, y) 5 mm and ( z) 3 mm in superfluid helium at 1.8 K. The insert was used to obtain the millimeter-sized fluorescence image of cell nuclei at 1.8 K without a sample exchange.
doi:10.1063/5.0107395 fatcat:2e63zpq3tvcjhdy6qwdcsnnjki