Dr Kent Shirer, Max Planck Institute for Chemical Physics of Solids, Dresden
I will present magnetoresistance data on high quality, focused ion beam (FIB)-fabricated microstructures of CeRhIn5, a strongly correlated metal which is antiferromagnetic below TN~3.8K due to the local 4f-moments of the cerium. Recently, we uncovered a field-induced state in this material above H~28T which is nematic in character [1]. During this experiment, we observed a curious discrepancy between the antiferromagnetic transition temperature when measured along the c- or a-axis of the structures prepared with the FIB. Given the potential role of magnetism in the high-field state, we investigated the evolution of the Néel temperature with a series of FIB-fabricated devices with cross sections that vary over multiple orders of magnitude, down to less than a square micron. We find that in our microstructured devices measured along the c-axis, the Néel temperature may be suppressed to nearly ~3.2K. I will discuss these results in context with FIB fabrication techniques and transport measurements in other Ce-115 materials.
[1] Ronning, F. et al. Nature 548, 313–317 (2017)