AlGaAs/GaAs quantum wire lasers fabricated by flow rate modulation epitaxy

Evidence of blocking effect on carrier trapping process by necking region in very narrow AlGaAs/GaAs V-grooved quantum wire structure

“…V-grooved quantum wire ͑QWR͒ structures have attracted much attention in recent years [1][2][3][4][5][6][7] due to the simplicity of their fabrication and prospects for device applications. The V-grooved QWR is fabricated by direct epitaxial growth on a V-grooved substrate.…”

First demonstration of the gain switching characteristics of an AlGaAs–GaAs V-grooved quantum wire laser

“…2 shows the time-resolved oscillation spectra of the QWR laser under (a) cw operation and (b) gain switching. Mode hopping from the lower subband energy-state (839 nm, corresponding to the ground state) to the higher state was found (830 nm, corresponding to the 2nd state) under cw operation (I = 1.2I th ) [9]. However, the emission spectra under gain switching comes up from the higher energy-state (831 nm) and then at the lower state (838 nm) with about 20 ps of time delay.…”

“…The oscillation wavelength under room temperature cw operation was 839 nm at threshold, but another spectrum due to band ®lling appeared either at 835 or at 830 nm, depending on driving conditions of the gain switching. More details of the laser characteristics will be found in [9].…”

“…This is probably due to the technical diculties in producing crystallographically immaculate QWR or QD. Structural imperfections such as heterointerface roughness and¯uctuations in the size and shape of the wires (or dots) lead to inhomogeneous broadening eects in the energy spectrum, which can wash out Recently, we have fabricated almost perfect QWR crystals where the surface roughness was about one mono-layer, by usinḡ ow rate modulation epitaxy [8], and thus, even made it possible to get the ®rst room temperature lasing from the ground states of the QWR laser [9].…”

High thermal stability of photoluminescence in a disordered quantum wire superlattice

“…V-grooved QWRs have attracted much attention in recent years [13][14][15][16][17][18][19][20][21] due to their simplicity of fabrication and prospects on device application. 13,22,23 The V-grooved QWR is fabricated by direct epitaxial growth on a V-grooved substrate, during which the EBE can be easily realized in the growth and lateral directions. Recently, based on improved epitaxial techniques, highly uniform GaAs/AlGaAs QWR-SL structures have been successfully fabricated by using the flow rate modulation epitaxy ͑FME͒ technique.…”