Strong enhancement of terahertz emission from GaAs in InAs/GaAs quantum dot structures

Journal Article · Mon Jun 08 04:00:00 EDT 2009 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3148670· OSTI ID:21294145

Estacio, Elmer; Pham, Minh Hong; Takatori, Satoru; Cadatal-Raduban, Marilou; Nakazato, Tomoharu; Shimizu, Toshihiko; Sarukura, Nobuhiko ^[1]; Somintac, Armando; Defensor, Michael; Awitan, Fritz Christian B; Jaculbia, Rafael B; Salvador, Arnel ^[2]; Garcia, Alipio ^[3]

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1. Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan)
2. National Institute of Physics, University of the Philippines, Diliman, Quezon City 1101 (Philippines)
3. Department of Physical Sciences, University of the Philippines, Baguio City 2600 (Philippines)

We report on the intense terahertz emission from InAs/GaAs quantum dot (QD) structures grown by molecular beam epitaxy. Results reveal that the QD sample emission was as high as 70% of that of a p-type InAs wafer, the most intense semiconductor emitter to date. Excitation wavelength studies showed that the emission was due to absorption in strained undoped GaAs, and corresponds to a two order-of-magnitude enhancement. Moreover, it was found that multilayer QDs emit more strongly compared with a single layer QD sample. At present, we ascribe the intense radiation to huge strain fields at the InAs/GaAs interface.

• OSTI ID: 21294145
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 23 Vol. 94; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ABSORPTION
CRYSTAL GROWTH
GALLIUM ARSENIDES
INDIUM ARSENIDES
MOLECULAR BEAM EPITAXY
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
THZ RANGE