Resolving nonlinear recombination dynamics in semiconductors via ultrafast excitation correlation spectroscopy: Photoluminescence versus photocurrent detection

Abstract

We explore the application of excitation correlation spectroscopy to detect nonlinear photophysical dynamics in two distinct semiconductor classes through time-integrated photoluminescence and photocurrent measurements. In this experiment, two variably delayed femtosecond pulses excite the semiconductor, and the time-integrated photoluminescence or photocurrent component arising from the nonlinear dynamics of the populations induced by each pulse is measured as a function of inter-pulse delay by phase-sensitive detection with a lock-in amplifier. We focus on two limiting materials systems with contrasting optical properties: a prototypical lead-halide perovskite (LHP) solar cell, in which primary photoexcitations are charge photocarriers, and a single-component organic-semiconductor diode, which features Frenkel excitons as primary photoexcitations. The photoexcitation dynamics perceived by the two detection schemes in these contrasting systems are distinct. Nonlinear-dynamic contributions in the photoluminescence detection scheme arise from contributions to radiative recombination in both materials systems, while photocurrent arises directly in the LHP but indirectly following exciton dissociation in the organic system. Consequently, the basic photophysics of the two systems are reflected differently when comparing measurements with the two detection schemes.

Submitted for publication

References in corpus (6)

• Charge separation by photoexcitation in semicrystalline polymeric semiconductors: An intrinsic or extrinsic mechanism?
• Are Shockley-Read-Hall and ABC models valid for lead halide perovskites?
• Incoherent population mixing contributions to phase-modulation two-dimensional coherent excitation spectra
• Frenkel biexcitons in hybrid HJ photophysical aggregates
• Ultrafast photocurrent and absorption microscopy of few-layer TMD devices isolate rate-limiting dynamics driving fast and efficient photoresponse
• Identifying incoherent mixing effects in the coherent two-dimensional photocurrent excitation spectra of semiconductors

Cited by in corpus (3)

• Exciton Bimolecular Annihilation Dynamics in Push-Pull Semiconductor Polymers
• Resolving exciton and polariton multi-particle correlations in an optical microcavity in the strong coupling regime
• Exciton-photocarrier interference in mixed lead-halide-perovskite nanocrystals