Scanning Probe Microscopy Combined with Low Temperature Cryogen-free Operation in an Ultra-High Vacuum High Field Environment

Scanning probe microscopy (SPM) is combined with cryogen-free operation in our innovative ultra-high vacuum (UHV) system with low temperatures reaching 4K and high magnetic fields up to 9T. Utilizing a unique internal vibration isolator and custom probe head, we have sufficiently reduced the vibration level of the cryostat pulse tube to operate SPMs thus solving the problem that typical cryogen-free systems are too noisy to operate SPMs. Our custom probe head is modular and accommodates interchangeable probes, such as STM, AFM, and MFM. Sample and probe conditioning is incorporated into the UHV system, particularly ion sputtering, e-beam film deposition, exfoliation, and heat treatment. The SPM head is transferable about the entire system, allowing for sample and probe insertion at room temperature with optical access. A novel low-profile vertical transfer mechanism enables transport of the SPM to the cryogen-free cryostat. By incorporating all these capabilities into one instrument, nano-scale characterization of low dimensional systems can be explored in an ultra-clean environment with controlled temperature and magnetic field.