PRL 104, 215503 (2010)

Bulk metallic glasses are brittle and fail with no plastic strain at
room temperature once shear bands propagate. How do metallic glasses
deform when the size is less than that of shear bands? Here we show
that Al90Fe5Ce5 metallic glass with a size <20  nm can be extremely elongated to ∼200%.
Remarkably, even an atomic chain was formed after sample necking, which
was never observed in metallic glasses. The unexpected ductility may
originate from the fast surface diffusion and the absence of shear band
formation, and may guide the development of ductile metallic glasses
for engineering applications.