Publications [#222967] of Henry Everitt

Papers Published
  1. {\"O}zg{\"u}r, {\"U}mit and Everitt, Henry O, Ultrafast carrier relaxation in GaN, In0.05Ga0.95N, and an In0.07Ga0.93N/In0.12Ga0.88N multiple quantum well, Physical Review B (Condensed Matter and Materials Physics), vol. 67 no. 15 (April, 2003), pp. 155308 [nph-data_query], [doi] .

    Room-temperature, wavelength-nondegenerate ultrafast pump/probe measurements were performed on GaN and InGaN epilayers and an InGaN multiple quantum well (QW) structure. Carrier relaxation dynamics were investigated as a function of excitation wavelength and intensity. Spectrally resolved sub-picosecond relaxation due to carrier redistribution and QW capture was found to depend sensitively on the wavelength of pump excitation. Moreover, for pump intensities above a threshold of 100 $\mu$J/cm2, all samples demonstrated an additional emission feature arising from stimulated emission (SE). SE is evidenced as accelerated relaxation (<10 ps) in the pump-probe data, fundamentally altering the redistribution of carriers. Once SE and carrier redistribution is completed, a slower relaxation of up to 1 ns for GaN and InGaN epilayers, and 660 ps for the multiple QW sample, indicates carrier recombination through spontaneous emission.