Harsh condition scanning probe microcopy vs. imaging detection of new magnetic structures and their topological protection

The scanning probe microscope has atomic resolution, which is a revolution in microscopy. But, it is sensitive to even weak vibration or sound (V/S) and requires well designed V/S isolation. However, many important researches must be performed in harsh conditions such as in ultra-strong water-cooled magnet (WM), cryogen-free (dry) superconducting magnet, dilution refrigerator or reactive solution. To this end, we have achieved high quality atomic resolution images in harsh and ultra-harsh conditions. Finally, we are successful in obtaining high clearance atomic resolution images in a WM [Ultramicroscopy 205(2019)20], dry magnet [Nano Res. 8(2015)3898] and active/reactive solution [Nano Res. 9(2016)2551; Nanoscale 8(2016)15142]. We will report these achievements as well as their applications in the imaging detections of new and weak magnetic structures with topological protection such as magnetic skyrmions in ultra-thin (only 5 layers of unit cells) oxide heterostructures BTO/SRO [Nature Mater. 17(2018)1087], artificially fabricated skyrmions [Adv. Funct. Mater. (2019)1907140], structural domain walls [Adv. Mater. 30(2018)1805353], multiply ordered electronic crystals [ACS Appl. Mater. Inter. 10(2018)20136] and phase competition in re-entrance process [Nature Comm. 6(2015)8980].