ESROP – Global + Max Planck Institute, University of Hamburg

Laser-driven plume formation is a process relevant to fluid dynamics, laser surgery, and materials processing. In photomechanical spallation, high-intensity laser pulses rapidly deposit energy into a liquid, triggering shock waves, phase transitions, and bubble formation. Although much is known about these phenomena, significant gaps remain in understanding how Newtonian fluids (e.g., glycerol and water) behave under ultrafast, high-strain-rate conditions. Traditionally, Newtonian fluids have been assumed to lack elasticity because they quickly dissipate deformation energy through viscous flow, at least at large time scales. However, research by Kayanattil et al. has challenged this view by demonstrating “rubber-like” elasticity in liquid glycerol during laser-driven free-surface flow under vacuum. In these experiments, the elastic response persists for microseconds—four orders of magnitude (ten thousand times) longer than the typical molecular relaxation time (t?)—and strongly influences bubble expansion and rupture. This metastable state suggests that collective molecular interactions can temporarily suppress energy dissipation, yielding solid-like behavior in a simple liquid. [4] While earlier studies noted shear elasticity at high frequencies or low strains, the large-strain, long-duration elastic responses observed at extreme strain rates (~106 s?¹) are unprecedented.[4] These results challenge conventional fluid mechanics and suggest that long-range molecular correlations are critical under such conditions.

Faculty Supervisor:

Arthur Chan

Student:

Partner:

Max Planck Institute

Discipline:

Physics

Sector:

Quantum Science; Technology; Other

University:

University of Toronto

Program: