Cross-Examination of Photoinitiated Carrier and Structural Dynamics of Black Phosphorus at Elevated Fluences
arXiv:2304.13869 · doi:10.1063/5.0193613
Abstract
Revived attention in black phosphorus (bP) has been tremendous in the past decade. While many photoinitiated experiments have been conducted, a cross-examination of bP's photocarrier and structural dynamics is still lacking. In this report, we provide such analysis by examining time-resolved data acquired using optical transient reflectivity and reflection ultrafast electron diffraction, two complementary methods under the same experimental conditions. At elevated excitation fluences, we find that more than 90% of the photoinjected carriers are annihilated within the first picosecond (ps) and transfer their energy to phonons in a nonthermal, anisotropic fashion. Electronically, the remaining carrier density around the band edges induces a significant interaction that leads to an interlayer lattice contraction in a few ps but soon diminishes as a result of the continuing loss of carriers. Structurally, phonon-phonon scattering redistributes the energy in the lattice and results in the generation of out-of-plane coherent acoustic phonons and thermal lattice expansion. Their onset times at ~6 ps are found to be in good agreement. Later, a thermalized quasi-equilibrium state is reached following a period of about 40-50 ps. Hence, we propose a picture with five temporal regimes for bP's photodynamics.
arXiv comment16 pages, 4 figures for the main text
References in corpus (18)
- Black phosphorus field-effect transistors
- Phosphorene: A New 2D Material with High Carrier Mobility
- High-mobility transport anisotropy and linear dichroism in few-layer black phosphorus
- Rediscovering Black Phosphorus: A Unique Anisotropic 2D Material for Optoelectronics and Electronics
- Fast and broadband photoresponse of few-layer black phosphorus field-effect transistors
- The Renaissance of Black Phosphorus
- Layer-dependent Band Alignment and Work Function of Few-Layer Phosphorene
- Interlayer electronic hybridization leads to exceptional thickness-dependent vibrational properties in few-layer black phosphorus
- Dynamical Evolution of Anisotropic Response in Black Phosphorus under Ultrafast Photoexcitation
- Large Frequency Change with Thickness in Interlayer Breathing Mode - Significant Interlayer Interactions in Few Layer Black Phosphorus
- Spatial-Temporal Imaging of Anisotropic Photocarrier Dynamics in Black Phosphorus
- Ultralow-frequency collective compression mode and strong interlayer coupling in multilayer black phosphorus
- Accessing the anisotropic non-thermal phonon populations in black phosphorus
- Anisotropic Nonequilibrium Lattice Dynamics of Black Phosphorus
- Intrinsic coherent acoustic phonons in indirect band gap semiconductors Si and GaP
- Non-equilibrium Band Broadening, Gap Renormalization and Band Inversion in Black Phosphorus
- Anisotropic Charge Carrier and Coherent Acoustic Phonon Dynamics of Black Phosphorus Studied by Transient Absorption Microscopy
- Ultrafast carrier-coupled interlayer contraction, coherent intralayer motions, and phonon thermalization dynamics of black phosphorus