Hole-level structure of double -doped quantum wells in Si: The influence of the split-off band

AbstractThis paper describes a study of the photoresponse of long-wavelength (LWIR) and mid-infrared (MWIR) p-type GaAs/AlGaAs quantum well infrared photodetectors (QWIPs) as a function of temperature and QWIP parameters. Using an 8x8 envelope-function model (EFA), we designed and calculated the optical absorption of several bound-to-continuum (BC) structures, with the optimum designs corresponding to the second light hole level (LH2) coincident with the top of the well. For the temperature-dependent study, one non-optimized LWIR and one optimized MWIR samples were grown by MBE and their photoresponse and absorption characteristics measured to test the theory. The theory shows that the placement of the LH2 resonance at the top of the well for the optimized sample and the presence of light-hole-like quasi-bound states within the heavy-hole continuum for the nonoptimized sample account for their markedly different thermal and polarization characteristics. In particular, the theory predicts that, for the LWIR sample, the LH-like quasi-bound states should lead to an increased Ppolarized photoresponse as a function of temperature. Our temperature dependent photoresponse measurements corroborate most of the theoretical findings with respect to the long-wavelength threshold, shape, and polarization and temperature dependence of the spectra.

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ELECTRON AND HOLE EFFECTIVE g FACTORS IN InAs/GaSb QUANTUM WELLS

International Journal of Nanoscience ◽

10.1142/s0219581x0300153x ◽

2003 ◽

Vol 02 (06) ◽

pp. 437-444 ◽

Cited By ~ 1

Author(s):

A. ZAKHAROVA ◽

S. T. YEN ◽

K. A. CHAO

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Quantum Wells ◽

Landau Level ◽

Heavy Hole ◽

Strong Dependence ◽

Zero Magnetic Field ◽

Electron Level ◽

Hole Level ◽

G Factors

We investigate the Landau level structures and the electron and hole effective g factors in InAs / GaSb quantum wells under electric and quantizing magnetic fields perpendicular to interfaces. In these structures, the lowest electron level in InAs can be below the highest heavy-hole level in GaSb at zero magnetic field B. Thus the electron and hole levels anticross with the increasing magnetic field and the strong dependence of the Landau level structures as well as g factors on B is obtained. We have found that the voltage across the structure and the lattice-mismatched strain also produce the essential changes in the Landau level structures as well as the electron and hole g factors.

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The energy level structure of a variety of one-dimensional confining potentials and the effects of a local singular perturbation

Canadian Journal of Physics ◽

10.1139/cjp-2015-0356 ◽

2015 ◽

Vol 93 (12) ◽

pp. 1588-1596 ◽

Cited By ~ 14

Author(s):

M.L. Glasser ◽

L.M. Nieto

Keyword(s):

Quantum Wells ◽

Level Structure ◽

Stark Spectroscopy ◽

Green Function Method ◽

Energy Level Structure ◽

One Dimensional ◽

Asymmetric Hybrid ◽

Delta Functions ◽

Quadratic Potentials

Motivated by current interest in quantum confinement potentials, especially with respect to the Stark spectroscopy of new types of quantum wells, we examine several novel one-dimensional singular oscillators. A Green function method is applied, the construction of the necessary resolvents is reviewed and several new ones are introduced. In addition, previous work on the singular harmonic oscillator model, introduced by Avakian et al. (Phys. Lett. A, 124, 233 (1987). doi:10.1016/0375-9601(87)90627-X0) is reproduced to verify the method and results. A novel feature is the determination of the spectra of asymmetric hybrid linear and quadratic potentials. As in previous work, the singular perturbations are modeled by delta functions.

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Spin dynamics and level structure of quantum-dot quantum wells

Physical Review B ◽

10.1103/physrevb.71.081309 ◽

2005 ◽

Vol 71 (8) ◽

Cited By ~ 20

Author(s):

Jesse Berezovsky ◽

Min Ouyang ◽

Florian Meier ◽

David D. Awschalom ◽

David Battaglia ◽

...

Keyword(s):

Quantum Dot ◽

Quantum Wells ◽

Spin Dynamics ◽

Level Structure

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Photoreflectance investigations of the energy level structure in GaInNAs-based quantum wells

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/16/31/006 ◽

2004 ◽

Vol 16 (31) ◽

pp. S3071-S3094 ◽

Cited By ~ 44

Author(s):

J Misiewicz ◽

R Kudrawiec ◽

K Ryczko ◽

G S k ◽

A Forchel ◽

...

Keyword(s):

Energy Level ◽

Quantum Wells ◽

Level Structure ◽

Energy Level Structure

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Characterization of GaAs/AlGaAs quantum wells and quantum wires by chemical lattice imaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171419 ◽

1994 ◽

Vol 52 ◽

pp. 736-737

Author(s):

A. Carlsson ◽

J.-O. Malm ◽

A. Gustafsson

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Quantum Wires ◽

Vapour Phase ◽

Quantitative Information ◽

Lattice Imaging ◽

Vapour Phase Epitaxy ◽

Metalorganic Vapour Phase Epitaxy ◽

High Resolution Images

In this study a quantum well/quantum wire (QW/QWR) structure grown on a grating of V-grooves has been characterized by a technique related to chemical lattice imaging. This technique makes it possible to extract quantitative information from high resolution images.The QW/QWR structure was grown on a GaAs substrate patterned with a grating of V-grooves. The growth rate was approximately three monolayers per second without growth interruption at the interfaces. On this substrate a barrier of nominally Al0.35 Ga0.65 As was deposited to a thickness of approximately 300 nm using metalorganic vapour phase epitaxy . On top of the Al0.35Ga0.65As barrier a 3.5 nm GaAs quantum well was deposited and to conclude the structure an additional approximate 300 nm Al0.35Ga0.65 As was deposited. The GaAs QW deposited in this manner turns out to be significantly thicker at the bottom of the grooves giving a QWR running along the grooves. During the growth of the barriers an approximately 30 nm wide Ga-rich region is formed at the bottom of the grooves giving a Ga-rich stripe extending from the bottom of each groove to the surface.

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Characterisation of multilayer materials using a position-sensitive atom probe

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176253 ◽

1990 ◽

Vol 48 (4) ◽

pp. 624-625

Author(s):

RAD Mackenzie ◽

G D W Smith ◽

A. Cerezo ◽

J A Liddle ◽

CRM Grovenor ◽

...

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Spatial Information ◽

Chemical Vapour ◽

Atom Probe ◽

Organic Chemical ◽

Growth Stages ◽

Multiple Quantum ◽

Quartz Wool ◽

Position Sensitive

The position sensitive atom probe (POSAP), described briefly elsewhere in these proceedings, permits both chemical and spatial information in three dimensions to be recorded from a small volume of material. This technique is particularly applicable to situations where there are fine scale variations in composition present in the material under investigation. We report the application of the POSAP to the characterisation of semiconductor multiple quantum wells and metallic multilayers.The application of devices prepared from quantum well materials depends on the ability to accurately control both the quantum well composition and the quality of the interfaces between the well and barrier layers. A series of metal organic chemical vapour deposition (MOCVD) grown GaInAs-InP quantum wells were examined after being prepared under three different growth conditions. These samples were observed using the POSAP in order to study both the composition of the wells and the interface morphology. The first set of wells examined were prepared in a conventional reactor to which a quartz wool baffle had been added to promote gas intermixing. The effect of this was to hold a volume of gas within the chamber between growth stages, leading to a structure where the wells had a composition of GalnAsP lattice matched to the InP barriers, and where the interfaces were very indistinct. A POSAP image showing a well in this sample is shown in figure 1. The second set of wells were grown in the same reactor but with the quartz wool baffle removed. This set of wells were much better defined, as can be seen in figure 2, and the wells were much closer to the intended composition, but still with measurable levels of phosphorus. The final set of wells examined were prepared in a reactor where the design had the effect of minimizing the recirculating volume of gas. In this case there was again further improvement in the well quality. It also appears that the left hand side of the well in figure 2 is more abrupt than the right hand side, indicating that the switchover at this interface from barrier to well growth is more abrupt than the switchover at the other interface.

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