Single-shot time resolved study of the photo-reversible phase transition induced in flakes of Ti3O5 nanoparticles at room temperature

- A unique metallic phase of λ-Ti3O5 is trapped within Ti3O5 nanoparticles.
- A reversible λ-Ti3O5 ↔ β-Ti3O5 phase transformation can be induced by laser pulses.
- The λ-Ti3O5 to β-Ti3O5 switching is established in ∼900 ns.
- The β-Ti3O5 to λ-Ti3O5 switching is established in less than 20 ns.
- Laser-induced heating strongly impacts the recorded kinetics.

We have performed single-shot time-resolved reflectivity measurements of the photo-reversible phase transition between λ- and β-phases of Ti3O5 nanoparticles at room temperature. These phase transitions are induced using nanosecond and millisecond laser pulses and are revealed by Raman spectroscopy. Upon nanosecond pulsed excitation, the λ- to β-phase transition is detected in about 900 ns, whereas the β- to λ-phase transition is noticed in less than 20 ns. The λ- to β-phase transition induced by quasi continuous wave laser happens on the millisecond time scale. We propose a scenario that accounts very well for the observed phenomena.

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