The Narrow Energy Gap Dilute Nitride Alloy In( AsN )
This study focuses on the electronic properties of dilute nitride alloys, specifically In(AsN). It examines the effects of nitrogen impurities and clusters on the band structure and energy levels, which significantly impact electron localization, mobility, and dynamics in optoelectronic applications. The research highlights the potential of InAs1-xNx grown on GaAs for infrared optoelectronics, as the admixing of nitrogen levels alters photoluminescence emission and enables significant tunability in the band gap energy. Applications include infrared gas sensing and laser technology.
The Narrow Energy Gap Dilute Nitride Alloy In( AsN )
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The Narrow Energy Gap Dilute Nitride Alloy In(AsN) A. Patanè,O. Makarovsky, W.H.M. Feu, L. Eaves School of Physics and Astronomy The University of Nottingham, UK http://www.nottingham.ac.uk/~ppzphy17/ Collaborators A. Krier and Q. Zhuang Physics Department, Un. of Lancaster, UK R. Airey EPSRC Facility for III-Vs, Un. of Sheffield, UK O. Dravchenko and M. Helm Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, Germany EU High Magnetic Field Labs, http://www.ru.nl/hfml
Comparing III-N-Vs GaAsN InPN InAsN N-level 0.2 eV N-pairs and clusters 0.4 eV CBE DE = 1 eV The band structure of III-V-Ns is determined by the distribution of energy levels due to N-impurities and N-clusters and their hybridization with the extended CB states. “Trends in the electronic structure of dilute nitride alloys” E.P. O’Reilly et al., SST24 033001 (2009)
Comparing III-N-Vs GaAsNInAsN Electron localization occurs if the CBE of the dilute ‘‘impurity’’ species lies below that of the host III-V, and the impurity electron mass, me, is heavy. GaNGaAsInN InAs CBE 0.3 eV N Electron mass me=0.13mo “Theory of the electronic structure…” A. Zunger et al., PRB64 115208 (2001) 0.02mo
This work Probing electronic properties • Tuning the band gap • Electron mobility and cyclotron mass • Electron coherence length • Hot electron dynamics
InAsN for IR-Optoelectronics InAs1-xNx on GaAs grown by MBE • Admixing of the N-levels with the band states of the III-V shifts the PL emission to longer l (>3mm ). • A large relative change of the band gap energy, Eg: • -DEg/Eg >10% at x=1% • Prospects for IR gas sensing, security applications, lasers… De la Mare et al., APL 95, 031110 ‘09 Kudrawiec et al. APL 94, 151902 ’09 J. Misiewicz (Wroclaw Un., Poland)
InAsN for IR-Optoelectronics InAs1-xNx on GaAs grown by MBE • Admixing of the N-levels with the band states of the III-V shifts the PL emission to longer l (>3mm ). • A large relative change of the band gap energy, Eg: • -DEg/Eg >10% at x=1% • Prospects for IR gas sensing, security applications, lasers… x=1% TEM, R. Beanland (UK) De la Mare et al., APL 95, 031110 ‘09
Hall Mobility • Nitrogen reduces the electron mobility. • m is limited by electron scattering by N-atoms, -pairs and–clusters. These effects are stronger in GaAsN than in InAsN due to the vicinity of the N-related states to the CBE. InAsN GaAsN Patanè et al. APL 93 252106 ’08 • Model for GaAsN predicts a strong reduction of the mobility and electron mean free path due to the N-levels. • Fahy et al. PRB 74, 035203 ‘06 GaAsN
Electron Cyclotron Mass InAs1-xNx The cyclotron mass increases with increasing x. Comparing the N-induced change of the mass in InAsN and GaAsN. T=100 K u= 2.9THz x=0% 0.4% 0.6% GaAsN LCINS, O’Reilly (me) 1.0% CR/PR GaAsN CR InAsN Patanè et al. PRB 80 115207 ’09
