Zinc blende structure GaAs/AlGaAs core-multishell nanowires(NWs)are grown on a GaAs(111)B substrate by a two-temperature process using an Au-catalyzed vapor-liquid-solid mechanism and metal organic chemical vapor depo...Zinc blende structure GaAs/AlGaAs core-multishell nanowires(NWs)are grown on a GaAs(111)B substrate by a two-temperature process using an Au-catalyzed vapor-liquid-solid mechanism and metal organic chemical vapor deposition,respectively.Defect-free radial heterostructure NWs are formed.It can be concluded that the NWs are grown with the main contributions from the direct impingement of the precursors onto the alloy droplets and little from adatom diffusion.The results indicate that the droplet acts as a catalyst rather than an adatom collector.The photoluminescence spectra reveal that the grown NWs have much higher optical efficiency than bare GaAs NWs.展开更多
Nitric oxide(NO)is cooled to 1 K in a seeded Ar supersonic molecular beam.NO molecules are ionized by one-color two-photon resonant enhanced multiphoton ionization(REMPI)process to form an ultracold plasma.The density...Nitric oxide(NO)is cooled to 1 K in a seeded Ar supersonic molecular beam.NO molecules are ionized by one-color two-photon resonant enhanced multiphoton ionization(REMPI)process to form an ultracold plasma.The density of the ionized molecules in the illuminated volume approaches to 1.5×10^(13) cm^(-3).Prompt electrons,plasma electrons and intact NO+ions are produced during this process.Experimental results confirm that the lifetime of this ultracold plasma is longer than 18.3μs.This is the first report of NO ultracold plasma with significant lifetime produced by one-color two-photon REMPI process.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2010CB327600the National High Technology R&D Program of China(2009AA03Z417)+2 种基金the National Natural Science Foundation of China(61020106007)New Century Excellent Talents in University(NCET-08-0736)the 111 Program of China(B07005).
文摘Zinc blende structure GaAs/AlGaAs core-multishell nanowires(NWs)are grown on a GaAs(111)B substrate by a two-temperature process using an Au-catalyzed vapor-liquid-solid mechanism and metal organic chemical vapor deposition,respectively.Defect-free radial heterostructure NWs are formed.It can be concluded that the NWs are grown with the main contributions from the direct impingement of the precursors onto the alloy droplets and little from adatom diffusion.The results indicate that the droplet acts as a catalyst rather than an adatom collector.The photoluminescence spectra reveal that the grown NWs have much higher optical efficiency than bare GaAs NWs.
基金Supported by the National Natural Science Foundation of China under Grant No 11304311。
文摘Nitric oxide(NO)is cooled to 1 K in a seeded Ar supersonic molecular beam.NO molecules are ionized by one-color two-photon resonant enhanced multiphoton ionization(REMPI)process to form an ultracold plasma.The density of the ionized molecules in the illuminated volume approaches to 1.5×10^(13) cm^(-3).Prompt electrons,plasma electrons and intact NO+ions are produced during this process.Experimental results confirm that the lifetime of this ultracold plasma is longer than 18.3μs.This is the first report of NO ultracold plasma with significant lifetime produced by one-color two-photon REMPI process.
