Accessing ultrastable glass via a bulk transformation.

As a medium to understand the nature of glass transition, ultrastable glasses have garnered increasing attention for their significance in fundamental science and technological applications. Most studies have produced ultrastable glasses through a surface-controlled process using physical vapor deposition. Here, we demonstrate an approach to accessing ultrastable glasses via the glass-to-glass transition, a bulk transformation that is inherently free from size constraints and anisotropy.