Quantum capture limited modulation bandwidth of quantum well, wire, and dot lasers

Abstract

We investigate the quantum capture limited modulation bandwidths of various lower-dimensional semiconductor lasers. It is shown that, for buried quantum well, wire, and dot lasers, the maximum bandwidth is proportional to the packing density of the active region. For the quantum wire lasers grown on V-grooved substrates, the maximum bandwidth is enhanced by the precapture of carriers from three-dimensional states to two-dimensional states before the capture into the one-dimensional states.

Intrinsic carrier capture time in deep-etched quantum-box (70 nm diameter) lasers at low temperature: An indication of extremely high quantum capture efficiency

“…5 Meanwhile, accurate control of QB distribution offers more chances to separate the intrinsic effect of the QB from the geometry related effect in the QB system through a systematical comparison of QB lasers with different packing densities of the QB. For lowdimensional quantum well and wide-wire lasers, the role of the packing density of the active medium on carrier capture dynamics has been identified both theoretically 14 and experimentally. [15][16][17] In order to investigate the intrinsic carrier dynamics of QB lasers, the influence of the geometry effect should be ruled out.…”

“…We know from previous work 14,16,17 that the effective carrier capture time cap e f f of lowdimensional semiconductor lasers consists of two parts. One is the carrier diffusion or drift time di f f , and the another is the scaled-up quantum capture time 14 which is equal approximately to the intrinsic ͑local͒ quantum capture time cap Q multiplied by the ratio of the volume of the threedimensional waveguide V 3D to the volume of the active medium V ac . That is, 14 cap e f f ϭ di f f ϩ(V 3D /V ac ) cap Q .…”

“…One is the carrier diffusion or drift time di f f , and the another is the scaled-up quantum capture time 14 which is equal approximately to the intrinsic ͑local͒ quantum capture time cap Q multiplied by the ratio of the volume of the threedimensional waveguide V 3D to the volume of the active medium V ac . That is, 14 cap e f f ϭ di f f ϩ(V 3D /V ac ) cap Q . Both terms are influenced by the laser geometry.…”

“…[15][16][17] In order to investigate the intrinsic carrier dynamics of QB lasers, the influence of the geometry effect should be ruled out. 14,16,17 In our previous work, 16 by measuring the emission dynamics of low-dimensional semiconductor lasers with different packing densities of the active medium, we developed a method to deduce the intrinsic quantum capture time in low-dimensional lasers. In this work, we apply this technique to deep-etched QB lasers.…”

Study of interwell carrier transport by terahertz four-wave mixing in an optical amplifier with tensile and compressively strained quantum wells

“…[1][2][3][4][5][6][7] Since Rideout et al 1 first proposed a well-barrier hole burning model, a number of theoretical analyses [2][3][4][5][6][7] and experimental investigations, including modulation response measurements, 5,6 picosecond pump-probe, 8,9 and intermodulation distortion measurements 10 have studied these processes.…”