Observation of electron confinement in InP/GaAs type-II ultrathin quantum wells

The issue of type-II band alignment for InP/GaAs heterostructure is addressed by means of simple layer architecture of ultrathin quantum wells (QWs). From specific signatures of the radiative recombination in type-II QWs especially the cube root dependence of blueshift in the lowest excitonic transition energy on excitation power in photoluminescence measurements indicates that the observed luminescence is originating from spatially separated electrons and holes. Such a blueshift is seen to increase with the QW thickness again confirming a type-II band alignment. A direct evidence of electron confinement in the conduction band of InP is provided by the capacitance voltage measurements.

[1]  V. Moshchalkov,et al.  Extended excitons and compact heliumlike biexcitons in type-II quantum dots. , 2009, 0910.4290.

[2]  Yia-Chung Chang,et al.  Submonolayer quantum dot infrared photodetector , 2009 .

[3]  Isaac Hernández-Calderón,et al.  Single-peak excitonic emission of CdSe ultra-thin quantum wells finished with fractional monolayers , 2008, Microelectron. J..

[4]  B. Alén,et al.  Optical investigation of type II GaSb/GaAs self-assembled quantum dots , 2007 .

[5]  Diana L. Huffaker,et al.  GaSb∕GaAs type II quantum dot solar cells for enhanced infrared spectral response , 2007 .

[6]  R. Magalhães-Paniago,et al.  Structural and optical properties of InP quantum dots grown on GaAs(001) , 2007 .

[7]  K. Rustagi,et al.  Temperature dependence of the lowest excitonic transition for an InAs ultrathin quantum well , 2006 .

[8]  Yang-Fang Chen,et al.  Properties of photoluminescence in type-II ZnMnSe∕ZnSeTe multiple quantum wells , 2004 .

[9]  K. H. Lee,et al.  Type-II interband transition of ZnS0.78Te0.22/ZnTe single quantum wells , 2004 .

[10]  M. Weyers,et al.  Determination of band offsets in strained In x Ga 1 − x As ∕ GaAs quantum wells by capacitance-voltage profiling and Schrödinger-Poisson self-consistent simulation , 2003, cond-mat/0307107.

[11]  G. Medeiros-Ribeiro,et al.  Aharonov-Bohm signature for neutral polarized excitons in type-II quantum dot ensembles. , 2003, Physical review letters.

[12]  Dieter Bimberg,et al.  450 meV hole localization in GaSb/GaAs quantum dots , 2003 .

[13]  S. Chua,et al.  Growth and optical properties of type-II InP/GaAs self-organized quantum dots , 2001 .

[14]  J. S. Wang,et al.  Carrier distribution and relaxation-induced defects of InAs/GaAs quantum dots , 2000 .

[15]  E. Gombia,et al.  Growth and electrical characteristics of InAs/GaAs quantum well and quantum dot structures , 2000 .

[16]  W. K. Liu,et al.  Thin Films: Heteroepitaxial Systems , 1999 .

[17]  G. Bastard,et al.  Excitonic recombination dynamics in shallow quantum wells , 1998 .

[18]  Optical properties of thin layers of GaAs strained to InP , 1998 .

[19]  C. Moon,et al.  Spatial resolution of capacitance-voltage profiles in quantum well structures , 1998 .

[20]  V. A. Karasyuk,et al.  ORIGIN OF SHARP LINES IN PHOTOLUMINESCENCE EMISSION FROM SUBMONOLAYERS OF INAS IN GAAS , 1997 .

[21]  Milton Feng,et al.  p‐type InGaAs/InP quantum well infrared photodetector with peak response at 4.55 μm , 1996 .

[22]  Sauer,et al.  Type-II band alignment in Si/Si1-xGex quantum wells from photoluminescence line shifts due to optically induced band-bending effects: Experiment and theory. , 1994, Physical review. B, Condensed matter.

[23]  Graham,et al.  Optical and structural properties of metalorganic-vapor-phase-epitaxy-grown InAs quantum wells and quantum dots in InP. , 1993, Physical review. B, Condensed matter.

[24]  Brandt,et al.  Exciton localization in submonolayer InAs/GaAs multiple quantum wells. , 1990, Physical review. B, Condensed matter.

[25]  A. Siegman,et al.  Room‐temperature photoluminescence times in a GaAs/AlxGa1−xAs molecular beam epitaxy multiple quantum well structure , 1985 .