Revealing charge carrier dynamics and transport in Te-doped GaAsSb and GaAsSbN nanowires by correlating ultrafast terahertz spectroscopy and optoelectronic characterization
Abstract
Recent advances in the growth of III-V semiconductor nanowires (NWs) hold great promise for nanoscale optoelectronic device applications. It is established that a small amount of nitrogen (N) incorporation in III-V semiconductor NWs can effectively red-shift their wavelength of operation and tailor their electronic properties for specific applications. However, understanding the impact of N incorporation on non-equilibrium charge carrier dynamics and transport in semiconducting NWs is critical in achieving efficient semiconducting NW devices. In this work, ultrafast optical pump-terahertz probe spectroscopy has been used to study non-equilibrium carrier dynamics and transport in Te-doped GaAsSb and dilute nitride GaAsSbN NWs, with the goal of correlating these results with electrical characterization of their equilibrium photo-response under bias and low-frequency noise characteristics. Nitrogen incorporation in GaAsSb NWs led to a significant increase in the carrier scattering rate, resulting in a severe reduction in carrier mobility. Carrier recombination lifetimes of 33 ± 1 picoseconds (ps) and 147 ± 3 ps in GaAsSbN and GaAsSb NWs, respectively, were measured. The reduction in the carrier lifetime and photoinduced optical conductivities are due to the presence of N-induced defects, leading to deterioration in the electrical and optical characteristics of dilute nitride NWs relative to the non-nitride NWs. Finally, we observed a very fast rise time of ∼2 ps for both NW materials, directly impacting their potential use as high-speed photodetectors.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 26, 2022
- Source ID
- 10.1088/1361-6528/ac7d61
Entities
People
- Dzmitry Yarotski
- Hirandeep Kuchoor
- Kendall Dawkins
- Long Yuan
- Min-cheol Lee
- Rabin Pokharel
- Rohit P Prasankumar
- Shanthi Iyer
- Shisir Devkota
- Yue Huang
Organizations
- Air Force Office of Scientific Research
- Center for Integrated Nanotechnologies
- Los Alamos National Laboratory
- National Nuclear Security Administration
- National Science Foundation
- Office of Science
- United States Department of Energy