Extremely stable temperature characteristics of 1550-nm band, p-doped, highly stacked quantum-dot laser diodes

Abstract

We fabricated 1.55-µm band, broad-area, p-doped, 30-layer stacked quantum-dot (QD) laser diodes (LDs) grown on an InP(311)B substrate via a delta-doping method employing a strain compensation technique. We doped Be atoms to a depth of 5 nm from the bottom of each QD layer. The concentration of Be atoms doped in the InGaAlAs spacer layer was 1 × 1018 cm−3. We observed a strong photoluminescence emission and a relatively coherent surface of QDs using atomic force microscopy. In addition, we observed that the fabricated QD-LDs had extremely stable temperature characteristics, and a characteristic temperature T0 of more than 2156 K was obtained.

1.5 μm quantum-dot diode lasers directly grown on CMOS-standard (001) silicon

“…The T0 value is anticipated to be dramatically increased by p-type modulation doping 27 . To investigate the wavelength stability, which is another superiority expected from QDs, primary lasing wavelengths versus temperature was also measured ( Supplementary Fig.…”

1.55-μm Lasers Epitaxially Grown on Silicon

“…7(b) presents temperature-dependent LI curves for a 20 μm × 1 mm device, with the maximum operation temperature up to 80℃. The characteristic temperature is calculated to be 58.7 K, which can be further improved by the p-type modulation doping of the QDs [37]. For reference, QD lasers grown on n-InP native substrate was fabricated simultaneously to evaluate the influence of defects in the InP buffer on the QD lasers.…”

1550 nm‐Band InAs/InGaAlAs Quantum Dot Distributed Feedback Lasers Grown on InP(311)B Substrate with Side‐Wall Gratings Simultaneously Fabricated with a Ridge Waveguide

“…Lasers diodes based on 1550 nm‐band InAs/InGaAlAs highly stacked QDs grown on InP(311)B substrates using a strain compensation crystal growth method are particularly promising in terms of very stable temperature characteristics and low thresholds. [ 12–14 ] At the same time, the authors’ group developed the QD compositional intermixing (QDI) technique by ion implantation and successive annealing to realize a QD laser monolithically integrated with QDI waveguides regionally tailored on the wafer. [ 15–19 ] From a viewpoint of a high‐coherence light source, distributed feedback (DFB) lasers based on 1550 nm InAs QDs on InP(100) substrates have achieved a narrow linewidths of 55 kHz.…”