High-optical-quality nanosphere lithographically formed InGaAs quantum dots using molecular beam epitaxy assisted GaAs mass transport and overgrowth

ABSTRACTThe spontaneous growth of GaN nanopillars on (111) Si by plasma assisted molecular beam epitaxy has been investigated. The growth of GaN nanopillars on Si is driven by the lattice mismatch strain energy on Si and the high surface energy of the nitrogen stabilized (0001) GaN surface. A higher growth rate of nanopillars compared to a compact GaN film suggests the diffusion of Ga atoms from the uncovered substrate areas to the nucleated GaN nanopillars. The GaN nanopillars were characterized by field-emission scanning electron microscopy (FE-SEM), photoluminescence, and micro Raman spectroscopy. SEM image revealed that average diameter of GaN nanopillars was in the range of 70-100nm and an average height of 600nm. The photoluminescence (PL) spectra indicate the good emission property of the nanopillars. The low temperate PL spectrum exhibited an emission peak at 3.428eV besides a sharp excitonic peak. PL and Raman spectra indicate that GaN nanopillars are fully relaxed from lattice and thermal strain.

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Highly uniform and high optical quality In[sub 0.22]Ga[sub 0.78]As/GaAs quantum wires grown on (221)A GaAs substrate by molecular beam epitaxy

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.1398539 ◽

2001 ◽

Vol 19 (5) ◽

pp. 1824 ◽

Cited By ~ 14

Author(s):

T. Nitta ◽

Y. Ohno ◽

S. Shimomura ◽

S. Hiyamizu

Keyword(s):

Molecular Beam Epitaxy ◽

Gaas Substrate ◽

Molecular Beam ◽

Quantum Wires ◽

Optical Quality ◽

High Optical Quality ◽

Highly Uniform

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Extremely uniform GaAs-AlGaAs heterostructure layers with high optical quality by molecular beam epitaxy

Journal of Crystal Growth ◽

10.1016/0022-0248(83)90377-9 ◽

1983 ◽

Vol 61 (2) ◽

pp. 393-396 ◽

Cited By ~ 5

Author(s):

T. Fujii ◽

S. Hiyamizu ◽

O. Wada ◽

T. Sugahara ◽

S. Yamakoshi ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Optical Quality ◽

High Optical Quality

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Optical and electrical properties of semi-insulating GaN:C grown by MBE

MRS Proceedings ◽

10.1557/proc-743-l10.7 ◽

2002 ◽

Vol 743 ◽

Cited By ~ 3

Author(s):

R. Armitage ◽

Qing Yang ◽

H. Feick ◽

S. Y. Tzeng ◽

J. Lim ◽

...

Keyword(s):

Electrical Properties ◽

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Transport Model ◽

Growth Conditions ◽

Optical Quality ◽

Optical And Electrical Properties ◽

High Optical Quality ◽

Pair Defect ◽

Additional Support

ABSTRACTSemi-insulating wurtzite GaN:C of high optical quality is obtained with CCl4or CS2 doping sources in plasma-assisted molecular-beam epitaxy in Ga-rich growth conditions. The highest resistivity (107Ω-cm) is found for [C] in the low 1018cm−3range. An increasing fraction of carbon appears to form electrically inactive pair defects for higher doping levels causing the concentration of uncompensated residual donors to be higher in films with [C] in the 1019cm−3range compared with [C] in the 1018cm−3range. Blue (2.9 eV) and yellow (2.2 eV) luminescence bands are associated with carbon-related defects, and additional support is provided for the association of the blue luminescence with the carbon-acceptor deactivating pair defect. Finally, the temperature dependence of the resistivity is described within the grain-boundary controlled transport model of Salzmanet al., Appl. Phys. Lett.76, 1431 (2000).

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Optical Quality of InAs/InP Quantum Dots on Distributed Bragg Reflector Emitting at 3rd Telecom Window Grown by Molecular Beam Epitaxy

Materials ◽

10.3390/ma14216270 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6270

Author(s):

Tristan Smołka ◽

Katarzyna Posmyk ◽

Maja Wasiluk ◽

Paweł Wyborski ◽

Michał Gawełczyk ◽

...

Keyword(s):

Quantum Dots ◽

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Internal Quantum Efficiency ◽

Radiative Lifetime ◽

Optical Quality ◽

Structural Quality ◽

Emission Quenching ◽

Inp Quantum Dots

We present an experimental study on the optical quality of InAs/InP quantum dots (QDs). Investigated structures have application relevance due to emission in the 3rd telecommunication window. The nanostructures are grown by ripening-assisted molecular beam epitaxy. This leads to their unique properties, i.e., low spatial density and in-plane shape symmetry. These are advantageous for non-classical light generation for quantum technologies applications. As a measure of the internal quantum efficiency, the discrepancy between calculated and experimentally determined photon extraction efficiency is used. The investigated nanostructures exhibit close to ideal emission efficiency proving their high structural quality. The thermal stability of emission is investigated by means of microphotoluminescence. This allows to determine the maximal operation temperature of the device and reveal the main emission quenching channels. Emission quenching is predominantly caused by the transition of holes and electrons to higher QD’s levels. Additionally, these carriers could further leave the confinement potential via the dense ladder of QD states. Single QD emission is observed up to temperatures of about 100 K, comparable to the best results obtained for epitaxial QDs in this spectral range. The fundamental limit for the emission rate is the excitation radiative lifetime, which spreads from below 0.5 to almost 1.9 ns (GHz operation) without any clear spectral dispersion. Furthermore, carrier dynamics is also determined using time-correlated single-photon counting.

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Structural and Optical Properties of InAsSbBi Grown by Molecular Beam Epitaxy on Offcut GaSb Substrates

Photonics ◽

10.3390/photonics8060215 ◽

2021 ◽

Vol 8 (6) ◽

pp. 215

Author(s):

Rajeev R. Kosireddy ◽

Stephen T. Schaefer ◽

Marko S. Milosavljevic ◽

Shane R. Johnson

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Optical Quality ◽

X Ray Diffraction ◽

Interface Quality ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Lateral Variations

Three InAsSbBi samples are grown by molecular beam epitaxy at 400 °C on GaSb substrates with three different offcuts: (100) on-axis, (100) offcut 1° toward [011], and (100) offcut 4° toward [011]. The samples are investigated using X-ray diffraction, Nomarski optical microscopy, atomic force microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The InAsSbBi layers are 210 nm thick, coherently strained, and show no observable defects. The substrate offcut is not observed to influence the structural and interface quality of the samples. Each sample exhibits small lateral variations in the Bi mole fraction, with the largest variation observed in the on-axis growth. Bismuth rich surface droplet features are observed on all samples. The surface droplets are isotropic on the on-axis sample and elongated along the [011¯] step edges on the 1° and 4° offcut samples. No significant change in optical quality with offcut angle is observed.

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