Scientists caught a solid material switching up its atomic structure in less than a trillionth of a second.
March 19, 2026
Original Paper
Direct observation of ultrafast amorphous-amorphous transitions indicated by bond stretching and angle bending in phase-change material GeTe
arXiv · 2603.17400
The Takeaway
Using ultra-fast electron pulses, researchers directly observed atoms in a 'glassy' material stretching and bending their bonds to shift from one disordered state to another. This is the first time we have seen the 'structural engine' behind how glass-like materials relax, a process that happens too fast for standard sensors to catch.
From the abstract
The intrinsic nature of glass states and glass transitions at the atomic scale remain a fundamental open question in condensed-matter physics and materials science. By combining femtosecond electron diffraction with time-dependent density-functional theory molecular dynamics simulations, we directly observe ultrafast amorphous-amorphous transitions in amorphous GeTe, manifested as rapid Ge-Te (Ge) bond stretching within 0.2 ps and subsequent angle bending of the Ge-Te (Ge)-Ge motif on a 0.5-2 ps