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Prolonged photo-carriers generated in a massive-and-anisotropic Dirac material
Munisa Nurmamat1, Yukiaki Ishida2, Ryohei Yori3
1Department of Physical Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8526, Japan. munisa627@hiroshima-u.ac.jp.
Scientific Reports
|June 15, 2018
Summary
Black phosphorus enables long-lived electron-hole pairs, crucial for excitonic condensation. This discovery highlights black phosphorus
Area of Science:
- Condensed Matter Physics
- Materials Science
- Optoelectronics
Background:
- Excitonic condensation in semiconductors is a quantum phenomenon.
- Carrier mass anisotropy is theorized to stabilize excitonic condensation by extending pair lifetimes.
Purpose of the Study:
- To investigate the dynamics of photo-generated carriers in black phosphorus.
- To confirm the suitability of black phosphorus for excitonic condensation applications.
Main Methods:
- Time- and angle-resolved photoemission spectroscopy (TR-ARPES).
- Exploration of electronic structure and carrier dynamics above the Fermi level.
Main Results:
- Observed massive-and-anisotropic Dirac-type electronic dispersions.
- Directly measured photo-carrier lifetimes exceeding 400 picoseconds.
- Confirmed long carrier lifetimes in black phosphorus.
Conclusions:
- Black phosphorus is a promising platform for achieving stable excitonic condensation.
- Findings pave the way for novel broadband mid-infrared optoelectronic devices based on black phosphorus.
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