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

TL;DR

This study uses STM to investigate the nanoscale structure, dynamics, and aging of metallic glass thin films, revealing heterogeneous surface behavior and demonstrating control over aging and surface modification at the nanoscale.

Contribution

It introduces STM-based techniques to analyze and manipulate aging and surface structures of metallic glass thin films at the nanoscale.

Findings

Surface clusters show heterogeneous hopping dynamics.

Low Hf concentration films have larger, slower aged clusters.

Argon sputtering resets surface to a fluctuating state.

Abstract

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.