Structural and optical studies of vertically aligned InAs/GaAs self-assembled quantum dots

Journal of Applied Physics

Volumn 90, Issue 12, 2001, Pages 6374-6378

  Migliorato, M A ^a   Wilson, L R ^a   Mowbray, D J ^a   Skolnick, M S ^a   Al Khafaji, M ^a   Cullis, A G ^a   Hopkinson, M ^a  

^a UNIVERSITY OF SHEFFIELD   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0035894079     PISSN: 00218979     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.1418003     Document Type: Article

References (26)

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19. Because the dots have a height significantly less than their width it is fluctuations of the former dimension which make the major contribution to the broadening of the electronic states.
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24. Results from an eight-band k.p calculation [O. Steir, M. Grundmann, and D. Bimberg, Phys. Rev. B 59, 5688 (1999)] show that the lowest hole state is predominantly heavy hole in character but contains ∼9% light-hole character (O. Stier private communication).
25. Actual tunneling rates are likely to be faster than the calculated values as a result of In diffusion from the dots into the GaAs barriers which will reduce the height of the tunneling barrier. See, for example, P. W. Fry, I. E. Itskevich, D. J. Mowbray, M. S. Skolnick, J. J. Finley, J. A. Barker, E. P. O'Reilly, L. R. Wilson, I. A. Larkin, P. A. Maksym, M. Hopkinson, M. Al-Khafaji, J. P. R. David, A. G. Cullis, G. Hill, and J. C. Clark, Phys. Rev. Lett. 84, 733 (2000).
26. For the 4 nm GaAs sample the separation between the tip of one dot and the base of the next dot in the stack is only ∼2 nm [see Fig. 2 (a)].