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Nanoparticles with various compositions of Fe–Rh have been fabricated by a solution phase chemical method and their magnetic properties characterized. After refining and size selection, the average particle size is about 2–5 nm by high-resolution transmission electron microscopy observation. From x-ray diffraction results, as-deposited FeRh nanopaticles reveal a typical chemically disordered fcc structure which can be transformed into CsCl-type structure through thermal annealing. Under selected annealing conditions, the coercivities, Hc, for FeRh nanoparticles measured at room temperature are increased, compared with that of their as-deposited states. This increasement in Hc is due to the crystallization of CsCl-type structure after annealing. Nanoparticles of Fe36Rh64 and Fe38Rh62 annealed at 600 °C for 6 h show the presence of the magnetic phase transitions, while those of Fe75Rh25 particles did not exhibit such a transition. [ABSTRACT FROM AUTHOR]

The origin of multilevel resistances of In3Sb1Te2 (IST) phase-change random access memory cell has been investigated with high-resolution transmission electron microscopy (HR-TEM). The HR-TEM indicates that the microstructure of IST in the programming volume changes from amorphous to InSb and amorphous at the first state, and InSb and InTe at the second state, and IST at the third state, which are fairly consistent with four different levels of resistance. The resistance difference between the amorphous and the IST is about four orders of magnitude. [ABSTRACT FROM AUTHOR]