Nanoscale Structure, Dynamics, and Aging Behavior of Metallic Glass Thin Films

Scanning tunneling microscopy (STM) observations resolve the structure and dynamics of metallic glass Cu${}_{100-x}$Hf${}_x$ films and demonstrate STM control of aging at a metallic glass surface. Surface clusters exhibit heterogeneous hopping dynamics. Low Hf concentration films feature an aged surface of larger, slower clusters. Argon ion-sputtering destroys the aged configuration, yielding a surface in constant fluctuation. STM can locally restore the relaxed state, allowing for nanoscale lithographic definition of aged sections.