Band Gap Renormalization, Carrier Multiplication, and Stark Broadening in Photoexcited Black Phosphorus

Abstract : We investigate black phosphorus by time- and angle-resolved photoelectron spectroscopy. The electrons excited by 1.57 eV photons relax down to a conduction band minimum within 1 ps. Despite the low band gap value, no relevant amount of carrier multiplication could be detected at an excitation density 3–6 × 1019 cm–3. In the thermalized state, the band gap renormalization is negligible up to a photoexcitation density that fills the conduction band by 150 meV. Astonishingly, a Stark broadening of the valence band takes place at an early delay time. We argue that electrons and holes with a high excess energy lead to inhomogeneous screening of near surface fields. As a consequence, the chemical potential is no longer pinned in a narrow impurity band.
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-02264121
Contributor : Christine Giorgetti <>
Submitted on : Tuesday, August 6, 2019 - 12:06:08 PM
Last modification on : Thursday, August 8, 2019 - 1:10:40 AM

Identifiers

Citation

Zhesheng Chen, Jingwei Dong, Evangelos Papalazarou, Marino Marsi, Christine Giorgetti, et al.. Band Gap Renormalization, Carrier Multiplication, and Stark Broadening in Photoexcited Black Phosphorus. Nano Letters, American Chemical Society, 2018, 19 (1), pp.488-493. ⟨10.1021/acs.nanolett.8b04344⟩. ⟨hal-02264121⟩

Share

Metrics

Record views

23