Size and shape effects on excitons and biexcitons in single InAs∕InP quantum dots

Single InAs quantum dots grown on an InP vicinal substrate are studied using polarized microphotoluminescence. The study of electron-hole exchange energy splitting reveals that the energy splitting is influenced by quantum confinement. The biexciton binding energies found for single dots grown on the vicinal substrate (around 2.4meV) are high as compared to those of dots grown on an InP(001) substrate and this is attributed to a difference in spatial confinement. Moreover, the quantum dot size is shown to influence directly the biexciton binding energy.

[1]  Philip J. Poole,et al.  Optical spectroscopy of single, site-selected, InAs/InP self-assembled quantum dots , 2004 .

[2]  A. Schliwa,et al.  Stability of Biexcitons in Pyramidal InAs/GaAs Quantum Dots , 2001 .

[3]  Takagahara.  Biexciton states in semiconductor quantum dots and their nonlinear optical properties. , 1989, Physical review. B, Condensed matter.

[4]  C. H. W. Barnes,et al.  Entangled two-photon source using biexciton emission of an asymmetric quantum dot in a cavity , 2002, cond-mat/0211689.

[5]  Rosa Weigand,et al.  Fine Structure of Biexciton Emission in Symmetric and Asymmetric CdSe/ZnSe Single Quantum Dots , 1999 .

[6]  V. Kulakovskii,et al.  Exciton complexes in In x Ga 1 − x A s / G a A s quantum dots , 1998 .

[7]  K. Nishi,et al.  Optical anisotropy in self-assembled InP quantum dots , 1999 .

[8]  E. Ivchenko.  Fine Structure of Excitonic Levels in Semiconductor Nanostructures , 1997 .

[9]  A. Zrenner.  A close look on single quantum dots , 2000 .

[10]  E. Tsitsishvili.  Fine Structure of Exciton Levels in Strained Quantum Dots , 2001 .

[11]  Lindberg,et al.  Biexcitons in semiconductor quantum dots. , 1990, Physical review letters.

[12]  N. Yokoyama,et al.  Observation of Exciton Transition in 1.3–1.55 µm Band from Single InAs/InP Quantum Dots in Mesa Structure , 2004 .

[13]  Mats-Erik Pistol,et al.  Optical and theoretical investigations of small InP quantum dots in GaxIn1-xP , 2003 .

[14]  A. Schliwa,et al.  Repulsive exciton-exciton interaction in quantum dots , 2003 .

[15]  J. Brault,et al.  Optical anisotropy and photoluminescence temperature dependence for self-assembled InAs quantum islands grown on vicinal (001) InP substrates , 2002 .

[16]  J. Brault,et al.  Optical properties of self-assembled InAs quantum islands grown on InP(001) vicinal substrates , 2001 .

[17]  D Bimberg,et al.  Size-dependent fine-structure splitting in self-organized InAs/GaAs quantum dots. , 2005, Physical review letters.

[18]  A. A. Gorbunov,et al.  Fine structure of neutral and charged excitons in self-assembled In(Ga)As/(Al)GaAs quantum dots , 2002 .