We observe the formation of metastable AuGe phases without quenching, during strictly isothermal nucleation and growth of Ge nanowires, using video-rate lattice-resolved environmental transmission electron microscopy. We explain the unexpected formation of these phases through a novel pathway involving large and abrupt variations in composition rather than temperature. The metastable catalyst has important implications for nanowire growth; and more broadly, the isothermal process provides both a new approach to growing and studying metastable phases, and a new perspective on their formation.
Citation: Physical Review Letters
Pub Type: Journals
Ge nanowire, environmental transmission electron microscope, nanoscale system