Understanding of recombination and photoconductivity dynamics of photogenerated charge carriers in GaInP NWs is essential for their optoelectronic applications. In this letter, we have studied a series of GaInP NWs with varied Ga composition. Time-resolved photoinduced luminescence, femtosecond transient absorption, and time-resolved THz transmission measurements were performed to assess radiative and nonradiative recombination and photoconductivity dynamics of photogenerated charges in the NWs. We conclude that radiative recombination dynamics is limited by hole trapping, whereas electrons are highly mobile until they recombine nonradiatively. We also resolve gradual decrease of mobility of photogenerated electrons assigned to electron trapping and detrapping in a distribution of trap states. We identify that the nonradiative recombination of charges is much slower than the decay of the photoluminescence signal. Further, we conclude that trapping of both electrons and holes as well as nonradiative recombination become faster with increasing Ga composition in GaInP NWs. We have estimated early time electron mobility in GaInP NWs and found it to be strongly dependent on Ga composition due to the contribution of electrons in the X-valley.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.nanolett.7b01159 | DOI Listing |
ACS Appl Nano Mater
January 2024
NanoLund and Division of Solid State Physics, Lund University, Box 118, Lund 221 00, Sweden.
We present vertically processed photovoltaic devices based on GaInP/InP tandem-junction III-V nanowires (NWs), contacting approximately 3 million NWs in parallel for each device. The GaInP and InP subcells as well as the connecting Esaki tunnel diode are all realized within the same NW. By processing GaInP/InP tandem-junction NW solar cells with varying compositions of the top junction GaInP material, we investigate the impact of the GaInP composition on the device performance.
View Article and Find Full Text PDFNanoscale
September 2022
Institut Photovoltaïque d'Ile-de-France (IPVF), Palaiseau F-91120, France.
With their unique structural, optical and electrical properties, III-V nanowires (NWs) are an extremely attractive option for the direct growth of III-Vs on Si for tandem solar cell applications. Here, we introduce a core-shell GaAs/GaInP NW solar cell grown by molecular beam epitaxy on a patterned Si substrate, and we present an in-depth investigation of its optoelectronic properties and limitations. We report a power conversion efficiency of almost 3.
View Article and Find Full Text PDFNanoscale
May 2019
School of Physics and Electronics, Hunan Key Laboratory for Supermicrostructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, Hunan 410083, P. R. China.
Wurtzite (WZ) GaAs nanowires (NWs) are of considerable interest for novel optoelectronic applications, yet high quality NWs are still under development. Understanding of their polytypic crystal structure and band structure is the key to improving their emission characteristics. In this work we report that the Ga1-xInxP shell provides ideal passivation on polytypic WZ GaAs NWs, producing high quantum efficiency (up to 80%).
View Article and Find Full Text PDFNanotechnology
December 2017
Department of Mathematics, Physics and Electrical Engineering, Halmstad University, PO Box 823, SE-301 18 Halmstad, Sweden. Solid State Physics and NanoLund, Lund University, PO Box 118, SE-221 00, Lund, Sweden.
Radial GaInP/AlGaInP nanowire array light-emitting diodes (LEDs) are promising candidates for novel high-efficiency solid state lighting due to their potentially large strain-free active emission volumes compared to planar LEDs. Moreover, by proper tuning of the diameter of the nanowires, the fraction of emitted light extracted can be significantly enhanced compared to that of planar LEDs. Reports so far on radial growth of nanowire LED structures, however, still point to significant challenges related to obtaining defect-free radial heterostructures.
View Article and Find Full Text PDFNanotoxicology
October 2016
b NanoLund, Lund University, Lund , Sweden .
Nanowires (NWs) have unique electrical and optical properties of value for many applications including lighting, sensing, and energy harnessing. Consumer products containing NWs increase the risk of NWs being released in the environment, especially into aquatic ecosystems through sewage systems. Daphnia magna is a common, cosmopolitan freshwater organism sensitive to toxicity tests and represents a likely entry point for nanoparticles into food webs of aquatic ecosystems.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!