Design of a scanning gate microscope in a cryogen-free dilution refrigerator

TL;DR

This paper presents the design of a scanning gate microscope compatible with a cryogen-free dilution refrigerator, achieving low vibrations suitable for sensitive measurements at millikelvin temperatures.

Contribution

It introduces a novel microscope design that mitigates cryocooler vibrations, enabling high-precision scanning probe experiments in cryogen-free systems.

Findings

Achieved root-mean-square vibrations of 0.8 nm at 3 K

Achieved root-mean-square vibrations of 2.1 nm at 15 mK

Demonstrated effective scanning in a cryogen-free environment

Abstract

We report on our design of a scanning gate microscope housed in a cryogen-free dilution refrigerator with a base temperature of 15 mK. The recent increase in efficiency of pulse tube cryocoolers has made cryogen-free systems popular in recent years. However, this new style of cryostat presents challenges for performing scanning probe measurements, mainly as a result of the vibrations introduced by the cryocooler. We demonstrate scanning with root-mean-square vibrations of 0.8 nm at 3 K and 2.1 nm at 15 mK in a 1 kHz bandwidth with our design.