title: Lasing characteristics of InP-based InAs quantum dots depending on InGaAsP waveguide conditions.
abstract: We report the influences of a dot-in-a-well structure with a thin GaAs layer and the thickness of a waveguide (WG) on the lasing characteristics of InAs quantum dots (QDs) based on InP. The QD laser diodes (QDLDs) consist of seven-stacked InAs QDs separated by a 10 nm-thick InGaAsP (1.15 μm, 1.15Q-InGaAsP) layer, which is further sandwiched by a 800 nm-thick 1.15Q-lnGaAsP WG (reference QDLD). For comparison, the InAs QDs were inserted into the InGaAsP (1.35 μm, 1.35Q-InGaAsP) quantum well embedded in the 1.15Q-InGaAsP matrix at the active layer. And a 2 monolayer (ML)-thick GaAs layer was additionally introduced right before the QD layer (GDWELL-LDs). Lasing emission from the reference QDLD with only the 1.15Q-InGaAsP structure was not observed at room temperature (RT). However, the lasing emission from the GDWELL-LDs was clearly observed at the wavelength of 1.46 μm at RT under continuous-wave (CW) mode. The threshold current density of the GDWELL-LD with the 800 nm-thick InGaAsP WG was measured to be 830 A/cm2, which was lower than that of the GDWELL-LD with the 200 nm-thick WG (900 A/cm2). Also, the slope efficiency of the GDWELL-LD was significantly improved with increasing thickness of the InGaAsP WG.
authors.forename: Byounggu
authors.initials: B
authors.lastname: Jo
authors.forename: Hyunjung
authors.initials: H
authors.lastname: Lee
authors.forename: Ilgyu
authors.initials: I
authors.lastname: Choi
authors.forename: Jiin
authors.initials: J
authors.lastname: Kim
authors.forename: Jin Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Won Seok
authors.initials: WS
authors.lastname: Han
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Song
authors.forename: Dae Kon
authors.initials: DK
authors.lastname: Oh
authors.forename: Sam Kyu
authors.initials: SK
authors.lastname: Noh
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Leem
mesh_terms: D001152:Arsenicals / Q000737:chemistry*; D007204:Indium / Q000737:chemistry*; D045663:Quantum Dots
chemical_list: D001152:Arsenicals; D007204:Indium; C076773:indium arsenide