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Electronic Structure and Optical Properties of Strained Type-II InAsxSb1-x/InAs Quantum Dots for Mid-Infrared Applications (2023)
Journal Article
Yeap, G. H., Rybchenko, S., Itskevich, I., Haywood, S., Carrington, P., & Krier, A. (2023). Electronic Structure and Optical Properties of Strained Type-II InAsxSb1-x/InAs Quantum Dots for Mid-Infrared Applications. Defect and Diffusion Forum, 425, 3-8. https://doi.org/10.4028/p-72o15p

InSb-based self-assembled quantum dots (SAQDs) are very promising for the mid-infrared (3-5 μm) optical range. We have analysed the electronic structure and optical properties of InAsxSb1- x/InAs dots. In this paper, we present the results of the mod... Read More about Electronic Structure and Optical Properties of Strained Type-II InAsxSb1-x/InAs Quantum Dots for Mid-Infrared Applications.

Small-vocabulary speech recognition using a silent speech interface based on magnetic sensing (2012)
Journal Article
Hofe, R., Ell, S. R., Fagan, M. J., Gilbert, J., Green, P. D., Moore, R. K., & Rybchenko, S. (2013). Small-vocabulary speech recognition using a silent speech interface based on magnetic sensing. Speech communication, 55(1), 22-32. https://doi.org/10.1016/j.specom.2012.02.001

This paper reports on word recognition experiments using a silent speech interface based on magnetic sensing of articulator movements. A magnetic field was generated by permanent magnet pellets fixed to relevant speech articulators. Magnetic field se... Read More about Small-vocabulary speech recognition using a silent speech interface based on magnetic sensing.

Modeling and analysis of intraband absorption in quantum-dot-in-well mid-infrared photodetectors (2012)
Journal Article
Hong, B. H., Rybchenko, S. I., Itskevich, I. E., Haywood, S. K., Tan, C. H., Vines, P., & Hugues, M. (2012). Modeling and analysis of intraband absorption in quantum-dot-in-well mid-infrared photodetectors. Journal of applied physics, 111(3), 033713. https://doi.org/10.1063/1.3684603

Intraband absorption in quantum-dot-in-a-well (DWELL) mid-infrared photodetectors is investigated using photocurrent spectroscopy and computationally cost-effective modeling linked to experimental data. The DWELL systems are challenging for modeling... Read More about Modeling and analysis of intraband absorption in quantum-dot-in-well mid-infrared photodetectors.

Speech synthesis parameter generation for the assistive silent speech interface MVOCA (2011)
Journal Article
Hofe, R., Ell, S. R., Fagan, M. J., Gilbert, J. M., Green, P. D., Moore, R. K., & Rybchenko, S. I. (2011). Speech synthesis parameter generation for the assistive silent speech interface MVOCA. Proceedings of the Annual Conference of the International Speech Communication Association, INTERSPEECH, 3009 - 3012

In previous publications, a silent speech interface based on permanent-magnetic articulography (PMA) has been introduced and evaluated using standard automatic speech recognition techniques. However, word recognition is a task that is computationally... Read More about Speech synthesis parameter generation for the assistive silent speech interface MVOCA.

Evaluation of a silent speech interface based on magnetic sensing (2010)
Presentation / Conference Contribution
Hofe, R., Ell, S. R., Fagan, M. J., Gilbert, J. M., Green, P. D., Moore, R. K., & Rybchenko, S. I. (2010, September). Evaluation of a silent speech interface based on magnetic sensing. Presented at INTERSPEECH 2010, 11th Annual Conference of the International Speech Communication Association

This paper reports on isolated word recognition experiments using a novel silent speech interface. The interface consist of magnetic pellets that are fixed to relevant speech articulators, and a set of magnetic field sensors that measure changes in t... Read More about Evaluation of a silent speech interface based on magnetic sensing.

Isolated word recognition of silent speech using magnetic implants and sensors (2010)
Journal Article
Gilbert, J. M., Rybchenko, S. I., Hofe, R., Ell, S. R., Fagan, M. J., Moore, R. K., & Green, P. (2010). Isolated word recognition of silent speech using magnetic implants and sensors. Medical engineering & physics, 32(10), 1189-1197. https://doi.org/10.1016/j.medengphy.2010.08.011

There are a number of situations where individuals wish to communicate verbally but are unable to use conventional means so called 'silent speech'. These include speakers in noisy and covert situations as well as patients who have lost their voice as... Read More about Isolated word recognition of silent speech using magnetic implants and sensors.

Modeling of intraband absorption for quantum dot-in-well structures with low computational cost (2010)
Journal Article
Hong, B. H., Rybchenko, S. I., Itskevich, I. E., Haywood, S. K., Tan, C. H., Vines, P., & Hugues, M. (2010). Modeling of intraband absorption for quantum dot-in-well structures with low computational cost. Journal of Physics: Conference Series, 242(1), Article 012013. https://doi.org/10.1088/1742-6596/242/1/012013

Much effort has been committed to development of quantum-dot-based infrared photodetectors owing to their potential for normal-incidence absorption and low dark current.Quantum-dot-in-well structures offer additional advantages, such as better wavele... Read More about Modeling of intraband absorption for quantum dot-in-well structures with low computational cost.

Strained arrays of colloidal nanoparticles: Conductance and magnetoresistance enhancement (2009)
Journal Article
Rybchenko, S. I., Dyab, A. K. F., Haywood, S. K., Itskevich, I. E., & Paunov, V. N. (2009). Strained arrays of colloidal nanoparticles: Conductance and magnetoresistance enhancement. Nanotechnology, 20(42), Article ARTN 425607. https://doi.org/10.1088/0957-4484/20/42/425607

Colloidal nanoparticles are very popular as building blocks of functional arrays for electronic and optical applications. However, there is a problem in achieving electrical conductivity in such nanoarrays due to their molecular shells. These shells,... Read More about Strained arrays of colloidal nanoparticles: Conductance and magnetoresistance enhancement.

Applicability of the kp method to modeling of InAs/GaSb short-period superlattices (2009)
Journal Article
Hong, B. H., Rybchenko, S. I., Itskevich, I. E., Haywood, S. K., Intartaglia, R., Tasco, V., Rainò, G., & De Giorgi, M. (2009). Applicability of the kp method to modeling of InAs/GaSb short-period superlattices. Physical review B: Condensed matter and materials physics, 79(16), 165323-1-165323-4. https://doi.org/10.1103/PhysRevB.79.165323

We investigate the long-standing controversy surrounding modeling of the electronic spectra of InAs/GaSb short-period superlattices (SPSLs). Most commonly, such modeling for semiconductor heterostructures is based on the kp method. However, this meth... Read More about Applicability of the kp method to modeling of InAs/GaSb short-period superlattices.

Type-II InAsxSb1-x/InAs quantum dots for midinfrared applications: Effect of morphology and composition on electronic and optical properties (2009)
Journal Article
Yeap, G. H., Rybchenko, S. I., Itskevich, I. E., & Haywood, S. K. (2009). Type-II InAsxSb1-x/InAs quantum dots for midinfrared applications: Effect of morphology and composition on electronic and optical properties. Physical review B: Condensed matter and materials physics, 79(7), 075305-1-075305-6. https://doi.org/10.1103/physrevb.79.075305

InSb-based self-assembled quantum dots are very promising for the midinfrared (3-5μm) optical range. We have analyzed the effect of geometry and composition on the electronic structure and optical spectra of InAsx Sb1-x /InAs dots. The calculated tra... Read More about Type-II InAsxSb1-x/InAs quantum dots for midinfrared applications: Effect of morphology and composition on electronic and optical properties.

L-band-related interband transition in InSb/GaSb self-assembled quantum dots (2008)
Book Chapter
Rybchenko, S. I., Gupta, R., Itskevich, I. E., & Haywood, S. K. (2008). L-band-related interband transition in InSb/GaSb self-assembled quantum dots. In Springer Proceedings in Physics; Narrow Gap Semiconductors 2007 (81-83). Springer Verlag. https://doi.org/10.1007/978-1-4020-8425-6_20

Effect of lattice-mismatch-induced strain on Γ-, X- and L-conduction-band edges in III-V self-assembled quantum dots has been calculated. The misfit strain is shown to strongly affect the band edges, leading to a possibility of Γ-L and Γ-X crossover.... Read More about L-band-related interband transition in InSb/GaSb self-assembled quantum dots.

Conduction-band crossover induced by misfit strain in InSb/GaSb self-assembled quantum dots (2007)
Journal Article
Rybchenko, S. I., Gupta, R., Lai, K. T., Itskevich, I. E., Haywood, S. K., Tasco, V., Deguffroy, N., Baranov, A. N., & Tournié, E. (2007). Conduction-band crossover induced by misfit strain in InSb/GaSb self-assembled quantum dots. Physical review B: Condensed matter and materials physics, 76(19), 0 - 0. https://doi.org/10.1103/physrevb.76.193309

We address the occurrence of conduction-band crossover in III-V self-assembled quantum dots solely due to misfit strain. Band structure analysis in terms of standard deformation-potential theory shows that Γ-X crossover can occur in the dot, while bo... Read More about Conduction-band crossover induced by misfit strain in InSb/GaSb self-assembled quantum dots.

Importance of aspect ratio over shape in determining the quantization potential of self-assembled zinc-blende III-V quantum dots (2007)
Journal Article
Rybchenko, S. I., Yeap, G., Gupta, R., Itskevich, I. E., & Haywood, S. K. (2007). Importance of aspect ratio over shape in determining the quantization potential of self-assembled zinc-blende III-V quantum dots. Journal of applied physics, 102(1), 013706. https://doi.org/10.1063/1.2752127

We have studied the effect of shape on the strain-modified electron/hole confinement potential in zinc-blende quantum dots (QDs), using standard deformation potential theory and an anisotropic continuum-elasticity approximation. Calculations were per... Read More about Importance of aspect ratio over shape in determining the quantization potential of self-assembled zinc-blende III-V quantum dots.

Tuning of electronic coupling between self-assembled quantum dots (2005)
Journal Article
Rybchenko, S., Itskevich, I., Skolnick, M. S., Cahill, J., Tartakovskii, A. I., Hill, G., & Hopkinson, M. (2005). Tuning of electronic coupling between self-assembled quantum dots. Applied physics letters, 87(3), 033104. https://doi.org/10.1063/1.1995953

Semiconductor self-assembled quantum dots (SAQDs) normally have zero-dimensional properties, but become coupled and acquire higher-dimensional character if the distance between the dots is small. Using photoluminescence spectroscopy under high hydros... Read More about Tuning of electronic coupling between self-assembled quantum dots.

High pressure as a tool to tune electronic coupling in self-assembled quantum dot nanostructures (2004)
Journal Article
Itskevich, I. E., Rybchenko, S. I., Andreev, A. D., Cahill, J., Tartakovskii, A. I., Skolnick, M. S., Hill, G., & Hopkinson, M. (2004). High pressure as a tool to tune electronic coupling in self-assembled quantum dot nanostructures. physica status solidi (b), 241(14), 3257-3262. https://doi.org/10.1002/pssb.200405235

High pressure provides an efficient way of controlling the electronic properties of semiconductor nanostructures. We use pressure to tune electronic coupling in stacks of self-assembled quantum dots (SAQDs). The coupling occurs as soon as the distanc... Read More about High pressure as a tool to tune electronic coupling in self-assembled quantum dot nanostructures.

Stark shift in electroluminescence of individual InAs quantum dots (2000)
Journal Article
Itskevich, I., Rybchenko, S., Tartakovskii, I., Stoddart, S., Levin, A., Main, P., Eaves, L., Henini, M., & Parnell, S. (in press). Stark shift in electroluminescence of individual InAs quantum dots. Applied physics letters, 76(26), 3932-3934. https://doi.org/10.1063/1.126825

We have fabricated light-emitting-diode heterostructure devices, in which a layer of InAs self-assembled quantum dots is embedded, with an active area of submicron size. In the electroluminescence spectra of these devices, we observed isolated narrow... Read More about Stark shift in electroluminescence of individual InAs quantum dots.

Electroluminescence from individual InAs self-assembled quantum dots (2000)
Journal Article
Itskevich, I., Stoddart, S., Rybchenko, S., Tartakovskii, I., Eaves, L., Parnell, S., Main, P., & Henini, M. (2000). Electroluminescence from individual InAs self-assembled quantum dots. Physica status solidi. A, Applied research, 178(1), 307-311. https://doi.org/10.1002/1521-396X%28200003%29178%3A1%3C307%3A%3AAID-PSSA307%3E3.0.CO%3B2-Y

Emission lines from individual InAs self-assembled quantum dots (SAQD) have been observed in electroluminescence spectra from small-area p-i-n light-emitting-diode heterostructure devices containing an embedded layer of SAQD. In the energy range whic... Read More about Electroluminescence from individual InAs self-assembled quantum dots.