Quantum dot p-i-n structure in an electric field

✍ Scribed by F. Yang; K. Hinzer; C.Ni. Allen; S. Fafard; G.C. Aers; Yan Feng; J. McCaffrey; S. Charbonneau

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 482 KB
• Volume: 25
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1998.0669

✦ Synopsis

Time-resolved photoluminescence (PL), steady-state PL, and electroluminescence (EL) techniques have been used to characterize the carrier relaxation processes and carrier escape mechanisms in self-assembled InAs/GaAs quantum dot (SAQD) p-i-n structures under reverse bias. The measurements were performed between 5 K and room temperature on a ring mesa sample as a function of bias. At 100 K, the PL decay time originating from the n = 1 SAQD decreases with increasing reverse bias from ∼3 ns under flat band condition to ∼400 ps for a bias of -3 V. The data can be explained by a simple model based on electron recombination in the quantum dots (QDs) or escape out of the dots. The escape can occur by one of three possible routes: direct tunneling out of the distribution of excited electronic levels, thermally assisted tunneling of ground state electrons through the upper excited electronic states or thermionic emission to the wetting layer.