Optical properties of bulk GaN crystals grown from solution at moderate pressure and temperature

Realization of compressively strained GaN films grown on Si(110) substrates by inserting a thin AlN/GaN superlattice interlayer

“…A strong single E 2 (high) peak at 567.6 cm À1 from the bulk GaN is observed in well agreement with the value in the literature. 22 On the other hand, our sample shows a double E 2 (high) peak feature by peak fitting, supporting the above HRXRD results. The left-side peak at 565.7 cm À1 showing a tensile strain state 23,24 is assigned to be from the 1st GaN layer, while the right-side peak at 568.3 cm À1 originates from the 2nd GaN layer indicating a compressive strain feature.…”

Optical probing of low-pressure solution grown GaN crystal properties

“…4 includes emission lines associated with recombination processes involving the annihilation of free excitons with holes deriving from the valence band A (FX A ) and from the valence band B (FX B ). Also observed, are the intense lines assigned to the annihilation of excitons bound to neutral shallow donors (Si and/or O) leaving the donors in the ground states (D1X A ) at 3.473 eV (FWHM of $ 350 meV, for sample C73-1), and the line related to the annihilation of exciton bound to a neutral unknown shallow acceptor (A1X A ) at 3.463 (FWHM of $320 meV, for sample C73-1) [22]. Note that, upon increasing of the relative intensity of the DAP band highlighted in Fig.…”