Download or read book Carrier Dynamics in Self organized Quantum Dots written by Gary Wang and published by . This book was released on 1997 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Self Organized Quantum Dots for Memories written by Tobias Nowozin and published by Springer Science & Business Media. This book was released on 2013-10-01 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today’s semiconductor memory market is divided between two types of memory: DRAM and Flash. Each has its own advantages and disadvantages. While DRAM is fast but volatile, Flash is non-volatile but slow. A memory system based on self-organized quantum dots (QDs) as storage node could combine the advantages of modern DRAM and Flash, thus merging the latter’s non-volatility with very fast write times. This thesis investigates the electronic properties of and carrier dynamics in self-organized quantum dots by means of time-resolved capacitance spectroscopy and time-resolved current measurements. The first aim is to study the localization energy of various QD systems in order to assess the potential of increasing the storage time in QDs to non-volatility. Surprisingly, it is found that the major impact of carrier capture cross-sections of QDs is to influence, and at times counterbalance, carrier storage in addition to the localization energy. The second aim is to study the coupling between a layer of self-organized QDs and a two-dimensional hole gas (2DHG), which is relevant for the read-out process in memory systems. The investigation yields the discovery of the many-particle ground states in the QD ensemble. In addition to its technological relevance, the thesis also offers new insights into the fascinating field of nanostructure physics.
Download or read book Electronic Properties of and Carrier Dynamics in Self organized Quantum Dots for Memories written by and published by . This book was released on 2013 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Carrier Dynamics in Self organized Quantum Dots for Memory Devices written by Martin Paul Geller and published by . This book was released on 2007 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Self Assembled Quantum Dots written by Zhiming M Wang and published by Springer Science & Business Media. This book was released on 2007-11-29 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: This multidisciplinary book provides up-to-date coverage of carrier and spin dynamics and energy transfer and structural interaction among nanostructures. Coverage also includes current device applications such as quantum dot lasers and detectors, as well as future applications to quantum information processing. The book will serve as a reference for anyone working with or planning to work with quantum dots.
Download or read book Time Resolved Electronic Relaxation Processes in Self Organized Quantum Dots written by and published by . This book was released on 2005 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have performed a comprehensive set of experiments on the dynamics of electrons and holes in semiconductor quantum dots, and a complete picture of the dynamics as a function of carrier density and temperature has emerged. Specifically, they have used two- and three-pulse femtosecond differential transmission spectroscopy to study the dependence of quantum dot carrier dynamics on temperature. At low temperatures and densities, the rates for relaxation between the quantum dot confined states and for capture from the barrier region into the various dot levels could be directly determined. For electron-hole pairs generated directly in the quantum dot excited state, relaxation is dominated by electron-hole scattering, and occurs on a 5-ps time scale. Capture times from the barrier into the quantum dot are on the order of 2 ps (into the excited state) and 10 ps (into the ground state). The phonon bottleneck was clearly observed in low-density capture experiments, and the conditions for its observation (namely, the suppression of electron-hole scattering for non-geminately captured electrons) were determined. As temperature increases beyond about 100 K, the dynamics become dominated by the reemission of carriers from the lower dot levels due to the large density of states in the wetting layer and barrier region. Measurements of the gain dynamics show fast (130-fs) gain recovery due to intradot carrier-carrier scattering, and picosecond-scale capture. Direct measurement of the transparency density versus temperature shows the dramatic effect of carrier reemission for the quantum dots to thermally activated scattering. The carrier dynamics at elevated temperatures are thus strongly dominated by the high density of the high-energy continuum states relative to the dot-confined levels. Deleterious hot carrier effects can be suppressed in quantum dot lasers by resonant tunneling injection.
Download or read book Study of Carrier Dynamics in Semiconductor Self assembled Quantum Dots written by 蘇立杰 and published by . This book was released on 2010 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spin and Carrier Dynamics in Self assembled InAs written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ultrafast Carrier Dynamics of InGaAs Quantum Dots in the High Carrier Density Regime written by Kyoungsik Kim and published by . This book was released on 2004 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ultrafast Carrier Dynamics in Semiconductor Self assembled Quantum Dots in the Low Carrier Density Regime written by Junji Urayama and published by . This book was released on 2002 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Carrier Dynamics in Quantum Well and Quantum Dot Lasers written by David J. Klotzkin and published by . This book was released on 1998 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Semiconductor Quantum Dots written by Yasuaki Masumoto and published by Springer Science & Business Media. This book was released on 2002-05-28 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Growth of Self Organized Quantum Dots / J.-S. Lee / - Excitonic Structures and Optical Properties of Quantum Dots / Toshihide Takagahara / - Electron-Phonon Interactions in Semiconductor Quantum Dots / Toshihide Takagahara / - Micro-Imaging and Single Dot Spectroscopy of Self Assembled Quantum Dots / Mitsuru Sugisaki / - Persistent Spectral Hole Burning in Semiconductor Quantum Dots / Yasuaki Masumoto / - Dynamics of Carrier Relaxation in Self Assembled Quantum Dots / Ivan V. Ignatiev, Igor E. Kozin / - Resonant Two-Photon Spectroscopy of Quantum Dots / Alexander Baranov / - Homogeneous Width of Confined Excitons in Quantum Dots - Experimental / Yasuaki Masumoto / - Theory of Exciton Dephasing in Semiconductor Quantum Dots / Toshihide Takagahara / - Excitonic Optical Nonlinearity and Weakly Correlated Exciton-Pair States / Selvakumar V. Nair, Toshihide Takagahara / - Coulomb Effects in the Optical Spectra of Highly Excited Semiconductor Quantum Dots / Selvakumar V. Nair / - Device ...
Download or read book Carrier Relaxation Dynamics in Self Assembled Quantum Dots written by V. Davydov and published by . This book was released on 2000 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: A novel technique to study carrier relaxation dynamics based on the artificial control of nonradiative losses by an external electric field is proposed. A clear evidence of phonon assisted relaxation as the main relaxation mechanism of hot electron-hole pairs in InP self-assembled quantum dots is found by the proposed method. Efficient one step relaxation processes with emission of acoustic and optical phonons are observed. These findings give new and important insight into the interaction of the electron-hole pairs in quantum dots with the phono subsystem.
Download or read book Impact of Ion Implantation on Quantum Dot Heterostructures and Devices written by Arjun Mandal and published by Springer. This book was released on 2017-06-02 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book looks at the effects of ion implantation as an effective post-growth technique to improve the material properties, and ultimately, the device performance of In(Ga)As/GaAs quantum dot (QD) heterostructures. Over the past two decades, In(Ga)As/GaAs-based QD heterostructures have marked their superiority, particularly for application in lasers and photodetectors. Several in-situ and ex-situ techniques that improve material quality and device performance have already been reported. These techniques are necessary to maintain dot density and dot size uniformity in QD heterostructures and also to improve the material quality of heterostructures by removing defects from the system. While rapid thermal annealing, pulsed laser annealing and the hydrogen passivation technique have been popular as post-growth methods, ion implantation had not been explored largely as a post-growth method for improving the material properties of In(Ga)As/GaAs QD heterostructures. This work attempts to remedy this gap in the literature. The work also looks at introduction of a capping layer of quaternary alloy InAlGaAs over these In(Ga)As/GaAs QDs to achieve better QD characteristics. The contents of this volume will prove useful to researchers and professionals involved in the study of QDs and QD-based devices.
Download or read book Self Assembled Quantum Dots written by Zhiming M. Wang and published by Springer. This book was released on 2008-11-01 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: This multidisciplinary book provides up-to-date coverage of carrier and spin dynamics and energy transfer and structural interaction among nanostructures. Coverage also includes current device applications such as quantum dot lasers and detectors, as well as future applications to quantum information processing. The book will serve as a reference for anyone working with or planning to work with quantum dots.
Download or read book Study of Quantum Confined Energy Levels in Self organized In Ga Al As Ga Al As Quantum Dots and Their Application to Mid infrared Sources and Detections written by Sanjay Krishna and published by . This book was released on 2001 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compound Semiconductors 2002 written by Marc Ilegems and published by CRC Press. This book was released on 2003-09-01 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major showcase for the compound semiconductor community, Compound Semiconductors 2002 presents an overview of recent developments in compound semiconductor physics and its technological applications to devices. The topics discussed reflect the significant progress achieved in understanding and mastering compound semiconductor materials and electronic and optoelectronic devices. The book covers heteroepitaxial growth, quantum confined emitters and detectors, quantum wires and dots, ultrafast transistors, and various compound materials.
