Ultrafast opacity in borosilicate glass induced by picosecond bursts of laser-driven ions

TL;DR

This study demonstrates that picosecond laser-driven ion bursts can induce ultrafast changes in borosilicate glass, enabling new investigations into rapid ion-matter interactions relevant to radiolysis and medical applications.

Contribution

It introduces the use of laser-driven ps ion bursts to study ultrafast ion-induced transients in matter, a capability not previously available with traditional ion sources.

Findings

Observed ultrafast electron-hole plasma formation with 3 ps rise time.

Measured decay time of 35 ps consistent with models.

Revealed high electron temperature and carrier density dynamics.

Abstract

Direct investigation of ion-induced dynamics in matter on picosecond (ps, 10-12 s) timescales has been precluded to date by the relatively long nanosecond (ns, 10-9 s) scale ion pulses typically provided by radiofrequency accelerators1. By contrast, laser-driven ion accelerators provide bursts of ps duration2, but have yet to be applied to the study of ultrafast ion-induced transients in matter. We report on the evolution of an electron-hole plasma excited in borosilicate glass by such bursts. This is observed as an onset of opacity to synchronised optical probe radiation and is characterised by the 3.0 +/- 0.8 ps ion pump rise-time . The observed decay-time of 35 +/- 3 ps i.e. is in excellent agreement with modelling and reveals the rapidly evolving electron temperature (>10 3 K) and carrier number density (>10 17cm-3). This result demonstrates that ps laser accelerated ion bursts are directly applicable to investigating the ultrafast response of matter to ion interactions and, in particular, to ultrafast pulsed ion radiolysis of water3-5, the radiolytic decompositions of which underpin biological cell damage and hadrontherapy for cancer treatment6.