Strong in-plane polarized intraband absorption in vertically aligned InGaAs/GaAs quantum dots

Adawi, A. M.; Zibik, E. A.; Wilson, L. R.; Lemai⁁tre, A.; Cockburn, J. W.; Skolnick, M. S.; Hopkinson, M.; Hill, G.; Liew, S. L.; Cullis, A. G.
May 2003
Applied Physics Letters;5/19/2003, Vol. 82 Issue 20, p3415
Academic Journal
We present a midinfrared absorption study of an n-i-n structure containing two planes of strongly coupled In[sub 0.5]Ga[sub 0.5]As self-assembled quantum dots. We find that the dominant absorption occurs for light polarized in the growth plane (E//xy), contrasting with uncoupled dots which exhibit stronger absorption for light polarized in the growth direction (E//z) in the same energy range. Results from the coupled dot sample indicate that the confinement length in the growth direction is increased, lowering the energy of the s-like ground state and hybridizing p[sub x,y]-like excited states and wetting layer states. A significantly increased normal incidence photocurrent signal is measured for the sample containing coupled dots, relative to samples containing up to 30 layers of uncoupled dots, confirming the enhancement of the normal incidence absorption.


Related Articles

  • Self-organization of quantum dots in multilayer InAs/GaAs and InGaAs/GaAs structures in submonolayer epitaxy. Tsyrlin, G. �.; Petrov, V. N.; Masalov, S. A.; Golubok, A. O. // Semiconductors;Jun99, Vol. 33 Issue 6, p677 

    The experimental results of RHEED and scanning tunneling microscopy investigations of multilayer structures of InGaAs/GaAs quantum dots, obtained by submonolayer epitaxy on singular and vicinal GaAS (100) substrates, are reported. The results presented show that spatial ordering of nano-objects...

  • 1.3μm Vertical Microcavities with InAs/InGaAs Quantum Dots and Devices Based on Them. Sakharov, A. V.; Krestnikov, I. L.; Maleev, N. A.; Kovsh, A. R.; Zhukov, A. E.; Tsatsul’nikov, A. F.; Ustinov, V. M.; Ledentsov, N. N.; Bimberg, D.; Lott, J. A.; Alferov, Zh. I. // Semiconductors;Jul2001, Vol. 35 Issue 7, p854 

    Various structures with optical microcavities and active layers based on InGaAs/GaAs quantum dots MBE-grown on GaAs substrates were studied theoretically and experimentally. LEDs for the 1.3 µm spectral range with narrow spectral characteristics and low light beam divergence were fabricated....

  • Optical and structural properties of InAsP ternary self-assembled quantum dots embedded in GaAs. Ribeiro, E.; Maltez, R. L.; Carvalho, W.; Ugarte, D.; Medeiros-Ribeiro, G. // Applied Physics Letters;10/14/2002, Vol. 81 Issue 16, p2953 

    We report on the growth of self-assembled ternary InAsP quantum dots embedded into GaAs. A comparison between average sizes and recombination energies for different dot species (InAs, InAsP, and InP) confirms the formation of the ternary alloy islands. By carefully changing the growth...

  • Spontaneous far-IR emission accompanying transitions of charge carriers between levels of quantum dots. Vorob�ev, L. E.; Firsov, D. A.; Shalygin, V. A.; Tulupenko, V. N.; Shernyakov, Yu. M.; Ledentsov, N. N.; Ustinov, V. M.; Alferov, Zh. I. // JETP Letters;2/25/98, Vol. 67 Issue 4, p275 

    The spontaneous emission of far-infrared radiation (??10�20�m) from diode structures with vertically coupled InGaAs/AlGaAs quantum dots is observed. This emission is due both to transitions of holes and electrons between size-quantization levels in quantum dots and to transitions from...

  • Effect of substrate misorientation on quantum-dot size distribution in the InAs/GaAs system. Vasil’ev, D. G.; Evtikhiev, V. P.; Tokranov, V. E.; Kudryashov, I. V.; Kochereshko, V. P. // Physics of the Solid State;May98, Vol. 40 Issue 5, p787 

    A study is reported of the effect of (001)GaAs substrate misorientation in the [010] direction on the distribution of MBE-grown self-assembled InAs/GaAs quantum dots in size and position in the GaAs matrix. Temperature-induced narrowing of the exciton photoluminescence line of a quantum-dot...

  • Temperature dependence of the photoluminescence of InGaAs/GaAs quantum dot structures without wetting layer. Sanguinetti, S.; Mano, T.; Oshima, M.; Tateno, T.; Wakaki, M.; Koguchi, N. // Applied Physics Letters;10/14/2002, Vol. 81 Issue 16, p3067 

    We analyze the photoluminescence temperature behavior of InGaAs/GaAs quantum dots grown by heterogeneous droplet epitaxy. Morphologically, these dots are nanocrystal InGaAs inclusions in the GaAs matrix, with a concave disk shape and, more important, no wetting layer is connecting the dots. The...

  • Characteristics of InGaAs quantum dots grown on tensile-strained GaAs1-xPx. Kim, N. H.; Ramamurthy, P.; Mawst, L. J.; Kuech, T. F.; Modak, P.; Goodnough, T. J.; Forbes, D. V.; Kanskar, M. // Journal of Applied Physics;5/1/2005, Vol. 97 Issue 9, p093518 

    InGaAs quantum dots (QDs) embedded in tensile-strained GaAs1-xPx (x=0.0–0.45) barrier layers are grown using low-pressure metal-organic chemical-vapor deposition. Variable-temperature photoluminescence (PL) measurement demonstrates that the lowest-energy QD transition can be blueshifted...

  • Effect of Modulation p-doping on the Optical Properties of Quantum Dot Laser Structure. Hasbullah, N. F.; David, J. P. R.; Mowbray, D. J. // AIP Conference Proceedings;3/30/2011, Vol. 1328 Issue 1, p136 

    Temperature dependence electroluminescence (EL) measurements have been performed on In(Ga)As/ GaAs quantum dot (QD) structures with varying amounts of modulation p-doping. It is found that the IEL decreases with increasing temperature with the size of reduction decreases with increasing doping...

  • A few-electron vertical In0.56Ga0.44As quantum dot with an insulating gate. Kita, T.; Chiba, D.; Ohno, Y.; Ohno, H. // Applied Physics Letters;12/3/2007, Vol. 91 Issue 23, p232101 

    Using an Al2O3 gate insulator by atomic layer deposition and air-bridge drain electrode, we fabricated a quantum dot with few electrons based on an In0.56Ga0.44As resonant tunneling diode structure. Artificial atomic properties manifested themselves in magnetotransport, enabling the...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics