Download or read book Charge Dynamics in Low Dimensional Prototype Correlated Systems a View with High energy X rays written by Md-Zahid Hasan and published by . This book was released on 2001 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Charge Dynamics in Low Dimensional Prototype Correlated Systems written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The electronic structure of Mott systems continues to be an unsolved problem in physics despite more than half-century of intense research efforts. Well-developed momentum-resolved spectroscopies such as photoemission and neutron scattering cannot directly address problems associated with the full Mott gap as angle-resolved photoemission probes the occupied states and neutrons do not couple to the electron's charge directly. Our observation of dispersive particle- hole pair excitations across the charge gap (effective Mott gap) in several low dimensional prototype Mott insulators using high resolution resonant inelastic x-ray scattering suggests that the excitations across the gap are highly anisotropic and momentum dependent. The results indirectly provide some information about the momentum dependence of unoccupied states in these correlated systems. The x-ray scattering results are complementary to the electron scattering results by the possibility of studying the excitations in the high momentum transfer regimes (near the zone boundaries and comers). This is also demonstrated in case of studying plasmons near the wave vector regime where Landau damping starts to dominate. X-ray scattering also allows one to probe the symmetry characters of localized electrons and the excitations through the strong polarization dependence of scattering near a core resonance. The study of charge-orbital localization is demonstrated in case of manganese oxides. Given its deeply bulk-sensitive and weak-coupling nature and the ability to probe dispersive behavior of charge fluctuations over several Brillouin zones, inelastic x-ray scattering shows the promise to become an important experimental tool to study the electronic structure of complex quantum systems.

Download or read book Charge Dynamics Near Phase Transitions in Two dimensional Systems written by Lily Joy Stanley and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Strongly correlated materials manifest some of the most intriguing behaviors found in condensed matter physics. However, their understanding remains a challenge because they cannot be described using standard theoretical approaches, as such systems are complex and typically have many competing degrees of freedom. Many strongly correlated systems are realized in layered or highly anisotropic materials, and they behave as effectively two-dimensional systems. When the dimensionality is reduced, fluctuations due to the competition between degrees of freedom are more pronounced and easier to observe. Anomalous transport properties are one of the hallmarks of strongly correlated materials; thus, charge transport measurements have proven remarkably effective for their study. This thesis focuses on three very different two-dimensional (2D) materials using charge transport to understand the origin of some of the observed behaviors. The electron system (ES) in Si metal-oxide-semiconductor field-effect transistors (MOSFETs) is a model strongly correlated system with only the interplay of Coulomb interactions and disorder. The insight from this simple system can help to build a more general picture of strongly correlated materials. Second, atomically thin layers of WSe2 produce a unique 2D system to study the universality of the correlated phenomena observed in Si MOSFETs. Finally, the Cu-O planes of La-214 compounds with charge and spin stripe order are complex materials, which behave effectively as 2D, with the interplay of many orders. By varying the dopant of the La-214 compound, the origin of the correlated behaviors can be probed. In the first two materials, the 2D MIT is controlled by applying a gate voltage. The existence of the 2D MIT is supported by an abundance of experimental data but remains poorly understood. Within experimental systems, both electron-electron interactions and disorder are present; however, the theory of their interplay is not fully developed. Studies performed on highly disordered Si MOSFETs suggest the importance of Coulomb interactions for the glassy dynamics observed at low electron densities. Therefore, the first study discussed in this thesis explores relaxations of conductivity in a strongly disordered 2DES with screened Coulomb interactions after the system is quenched-revealing the necessity of long-range Coulomb interactions for the existence of the collective (glassy) relaxation dynamics. Additionally, we have shown that, in the 2DES of the Si MOSFET weakly thermally coupled to the environment, abnormally long relaxations are observed in the presence of short-range interactions, suggesting that the system is in the proximity to a many-body-localized phase. Thus our results also demonstrate a promising new platform for exploring the breakdown of thermalization and MBL in real materials. Evidence of quantum criticality associated with the MIT has been almost exclusively studied in Si MOSFETs. Our second study reveals quantum criticality in WSe2 field-effect transistors showing that transition metal dichalcogenides are viable systems for the low-temperature investigation of the 2D MIT. Our scaling analysis found that the critical exponents agree with those found in low-disordered Si MOSFETs in the presence of local magnetic moments. These findings pave the way for further studies of the fundamental quantum mechanical properties of 2D transition metal dichalcogenides. The final study focuses on fluctuations of charge order (CO) and the magnetoresistance (MR) of stripe-ordered La-214 cuprates. The dynamics of CO are thought to be relevant for the unconventional properties of the normal state and high-temperature superconductivity. We report observations of dynamic charge stripes close to the charge order (and structural) transition in response to temperature perturbations but absent in magnetic field in La1.875Ba0.125CuO4. These dynamic behaviors are only observed when the transition is approached from the charge-ordered state. Additionally, a comparative analysis of the MR of several La-214 single crystals is presented to establish which behaviors are characteristic of the family of materials as opposed to dopant specific. Together, these three studies contribute to understanding the complex interplay of orders found in strongly correlated materials.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2006 with total page 886 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Annual Commencement written by Stanford University and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Attosecond Molecular Dynamics written by Marc J J Vrakking and published by Royal Society of Chemistry. This book was released on 2018-08-31 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Attosecond science is a new and rapidly developing research area in which molecular dynamics are studied at the timescale of a few attoseconds. Within the past decade, attosecond pump-probe spectroscopy has emerged as a powerful experimental technique that permits electron dynamics to be followed on their natural timescales. With the development of this technology, physical chemists have been able to observe and control molecular dynamics on attosecond timescales. From these observations it has been suggested that attosecond to few-femtosecond timescale charge migration may induce what has been called "post-Born-Oppenheimer dynamics", where the nuclei respond to rapidly time-dependent force fields resulting from transient localization of the electrons. These real-time observations have spurred exciting new advances in the theoretical work to both explain and predict these novel dynamics. This book presents an overview of current theoretical work relevant to attosecond science written by theoreticians who are presently at the forefront of its development. It is a valuable reference work for anyone working in the field of attosecond science as well as those studying the subject.

Download or read book Energy Research Abstracts written by and published by . This book was released on 1994-11 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Condensed Matter Field Theory written by Alexander Altland and published by Cambridge University Press. This book was released on 2010-03-11 with total page 785 pages. Available in PDF, EPUB and Kindle. Book excerpt: This primer is aimed at elevating graduate students of condensed matter theory to a level where they can engage in independent research. Topics covered include second quantisation, path and functional field integration, mean-field theory and collective phenomena.

Download or read book American Doctoral Dissertations written by and published by . This book was released on 2001 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Novel NMR and EPR Techniques written by J. Dolinsek and published by Springer. This book was released on 2006-09-11 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: A survey of recent research in the fields of condensed matter physics and chemistry based on novel NMR and ESR techniques. Applications include quantum computing, metal nanoparticles, low dimensional magnets, fullerenes as atomic cages, superconductors, porous media, and laser assisted studies. The book is dedicated to Professor Robert Blinc, on the occasion of his seventieth birthday, in appreciation of his remarkable scientific accomplishments in the NMR of condensed matter.

Download or read book Physics of Low Dimensional Systems written by José L. Morán-López and published by Springer Science & Business Media. This book was released on 2001-05-31 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains contributions on some of the most important and current topics on the physics of low dimensional systems. The main emphasis is on the magnetic properties of surfaces, thin films, and atomic clusters. State-of-the-art techniques are discussed in detail. Techniques for the production and measurement of nanostructures are discussed, and pioneering contributions on the effect on health of these particles are presented. Important studies on semiconductor nanostructures are addressed as well as aerosol systems.

Download or read book Journal of the Physical Society of Japan written by and published by . This book was released on 2008 with total page 1616 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Open Problems in Strongly Correlated Electron Systems written by Janez Bonca and published by Springer Science & Business Media. This book was released on 2001-04-30 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Research Workshop, Bled, Slovenia, 26-30 April 2000

Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1982 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technology for Large Space Systems written by and published by . This book was released on 1989 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Space Station Systems written by and published by . This book was released on 1986 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: