Reconstructing charge-carrier dynamics in porous silicon membranes from time-resolved interferometric measurements

Research output: Contribution to journalArticle

Colleges, School and Institutes

Abstract

We performed interferometric time-resolved simultaneous reflectance and transmittance measurements to investigate the carrier dynamics in pump-probe experiments on thin porous silicon membranes. The experimental data was analysed by using a method built on the Wentzel-Kramers-Brillouin approximation and the Drude model, allowing us to reconstruct the excited carriers’ non-uniform distribution in space and its evolution in time. The analysis revealed that the carrier dynamics in porous silicon, with ~50% porosity and native oxide chemistry, is governed by the Shockley-Read-Hall recombination process with a characteristic time constant of 375 picoseconds, whereas diffusion makes an insignificant contribution as it is suppressed by the high rate of scattering.

Details

Original languageEnglish
Article number17172
JournalScientific Reports
Volume8
Publication statusPublished - 21 Nov 2018

Keywords

  • Silicon, Ultrafast photonics