Hole diffusivity in GaAsBi alloys measured by a picosecond transient grating technique

We applied a time-resolved transient grating technique for investigation of nonequilibrium carrier dynamics in GaAs1−xBix alloys with x=0.025–0.063. The observed decrease in carrier bipolar diffusivity with lowering temperature and its saturation below 80 K revealed a strong localization of nonequilibrium holes. Thermal activation energy ΔEa=46 meV of diffusivity and low hole mobility value μh=10–20 cm2/V s at room temperature confirmed the hybridization model of the localized Bi states with the valence band of GaAs. Nonlinear increase in carrier recombination rate with the Bi content, 1/τR∝Bi(x)3.2 indicated an increasing structural disorder in the alloy.

[1]  M. Koch,et al.  Clustering effects in Ga(AsBi) , 2010 .

[2]  A. Mascarenhas,et al.  Electron Hall Mobility in GaAsBi , 2009 .

[3]  T. Tiedje,et al.  Composition dependence of photoluminescence of GaAs1-xBix alloys , 2009 .

[4]  M. Henini,et al.  Carrier localization in GaBiAs probed by photomodulated transmittance and photoluminescence , 2009 .

[5]  T. Tiedje,et al.  Bi isoelectronic impurities in GaAs , 2008 .

[6]  A. Krotkus,et al.  Valence band anticrossing in GaBixAs1−x , 2007 .

[7]  A. Krotkus,et al.  Characterization of low-temperature molecular-beam-epitaxy grown GaBiAs layers , 2007 .

[8]  David G. Cooke,et al.  Electron mobility in dilute GaAs bismide and nitride alloys measured by time-resolved terahertz spectroscopy , 2006 .

[9]  L. Wang,et al.  Similar and dissimilar aspects of III-V semiconductors containing Bi versus N , 2005 .

[10]  Michael S. Shur,et al.  Carrier diffusion and recombination in highly excited InGaN/GaN heterostructures , 2005 .

[11]  K. Jarašiūnas,et al.  Nonequilibrium carrier dynamics in heavily p-doped GaAs , 2004 .

[12]  W. R. Tribe,et al.  High resistivity annealed low-temperature GaAs with 100 fs lifetimes , 2003 .

[13]  R. Aleksiejūnas,et al.  Determination of free carrier bipolar diffusion coefficient and surface recombination velocity of undoped GaN epilayers , 2003 .

[14]  Ingrid Wilke,et al.  Carrier dynamics in low-temperature grown GaAs studied by terahertz emission spectroscopy , 2001 .

[15]  P. Kordos,et al.  Hall mobility analysis in low‐temperature‐grown molecular‐beam epitaxial GaAs , 1996 .

[16]  Gerard Mourou,et al.  Subpicosecond carrier lifetime in GaAs grown by molecular beam epitaxy at low temperatures , 1991 .

[17]  C. A. Hoffman,et al.  Measurement of surface recombination velocity in semiconductors by diffraction from picosecond transient free‐carrier gratings , 1978 .

[18]  R. A. Faulkner.  Toward a Theory of Isoelectronic Impurities in Semiconductors , 1968 .

[19]  D. G. Thomas,et al.  Isoelectronic Donors and Acceptors , 1966 .

[20]  A. Krotkus,et al.  Growth and characterization of GaBiAs epilayers , 2008 .