Photoluminescence and lasing properties of InAs/GaAs quantum dots grown by metal-organic chemical vapour deposition

Photoluminescence (PL) and lasing properties of InAs/GaAs quantum dots (QDs) with direrent growth procedures prepared by metalorganic chemical vapour deposition are studied. PL measurements show that the low growth rate QD sample has a larger PL intensity and a narrower PL line width than the high growth rate sample. During rapid thermal annealing, however, the lowgrowth rate sample shows a greater blue shift of PL peak wave length. This is caused by the larger InAs layer thickness which results from the larger 2-3 dimensional transition critical layer thickness for the QDs in the low-growth-rate sample. A growth technique including growth interruption and in-situ annealing, named indium flush method, is used during the growth of GaAs cap layer, which can flatten the GaAs surface effectively. Though the method results in a blue shift of PL peak wavelength and a broadening of PL line width, it is essential for the fabrication of room temperature working QD lasers.

National Natural Science Foundation of China 60706009 90401025607360366077702160476009National Key Basic Research Program of China 2006CB604901 2006CB604902 National High Technology Research and Development Program of China 2006AA01Z256 2007AA03Z419 2007AA03Z417 Project supported by the National Natural Science Foundation of China (Grant Nos 60706009, 90401025, 60736036, 60777021 and 60476009), the National Key Basic Research Program of China (Grant Nos 2006CB604901 and 2006CB604902) and the National High Technology Research and Development Program of China (Grant Nos 2006AA01Z256, 2007AA03Z419 and 2007AA03Z417).