The instrument is designed as an insert to commercial apparatus PPMS. In combination with the PPMS 14 apparatus, it allows measuring in the temperature range 4–340 K and in the magnetic fields up to 14 T. The whole PPMS 14 cryostat is placed in an antidumping frame in order to minimize noise.
Typical use: Temperature dependence of surface topography (e.g. formation of wrinkles) or imaging of magnetic domains at various temperatures and magnetic fields.
Parameters of the microscope:
- Fine scanning range: ~ 15 x 15 x 2 µm3 @ 4 K
- AFM Z-noise smaller than 120 pm (@ 4 K, rms, 5.12 ms sample time, feedback enabled)
- Z-deflection noise smaller than 3.0 pm/√Hz
- MFM Phase noise (bandwidth 1 kHz, rms): < 0.5°
- MFM signal-to-noise ratio > 20:1 (bandwidth 100Hz)
Where to use it?
Low temperature AFM/MFM method is available in the following cryostats:
Fig. 1: Magnetic domains of HDD at 4 K
Fig. 2: The time dependent magnetization process of SrRuO3 thin film, taken from M. Zahradník et al. / Materials and Design 187 (2020) 108390