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Althorpe, Stuart C. "Bound state calculations for van der Waals dimers." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319937.
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Kana'ah, A. "ODMR studies of bound excitons in GaP." Thesis, University of Hull, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376371.
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Hart, A. C. D. "An algebraic approach to bound state quantum field theory." Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233666.
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Dragan, Valer Carleton University Dissertation Physics. "Relativistic bound state equations for mesons in light-front momentum space." Ottawa, 1995.
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Nordling, Emil. "Generation of the Bound Entangled Smolin State and Entanglement Witnesses for Low-Dimensional Unitary Invariant States." Thesis, Uppsala University, Theoretical Physics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-130039.
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<p>Quantum entanglement is employed as a resource throughout quantum information science. However, before entanglement can be put to intelligent use, the issues of its production and detection must be considered. This thesis proposes four schemes for producing the bound entangled Smolin state. Three of these schemes produce the Smolin state by means of general quantum gates acting on different initial states - an all-zero state, a GHZ-state and two combined Bell states. The fourth scheme is based on one-qubit operations acting on two-photon states produced by SPDC. Furthermore, a maximum overlap entanglement witness detecting entanglement in the Smolin state is derived. This witness is measurable in three measurement settings with the maximal noise tolerance p=2/3. Lastly, simplified entanglement witnesses for the 4-, 6- and 8-qubit unitary invariant states are derived. These witnesses are measurable in three measurement settings with noise tolerances p=0.1802..., p=0.1502... and p=0.0751..., respectively.</p>
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Jentschura, Ulrich [Verfasser]. "Quantum Electrodynamic Bound-State Calculations and Large-Order Perturbation Theory / Ulrich Jentschura." Aachen : Shaker, 2003. http://d-nb.info/1174514426/34.
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Martin, Timothy James Semple. "UNIVERSAL BINDING AND RECOIL CORRECTIONS TO BOUND STATE g-FACTORS." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/810.
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The gyromagnetic ratio of bound particles is an active field of experimental and theoretical research. Early measurements of corrections to the bound g-factor came from experiments involving hydrogen-like ions. As the sensitivity of such experiments has increased, it has become possible to instead use them to measure the electron-ion mass ratio -- but only if the theoretical bound g-factor is known with sufficient precision for these systems. By constructing an effective nonrelativistic Lagrangian, we derive leading order binding and recoil corrections for systems comprised of particles with arbitrary spin.
Lagrangians for spin one-half and spin one-theories are developed, before moving on to the more general case of arbitrary spin. In each case, an effective nonrelativistic Lagrangian taking into account all relevant terms is constructed. The coefficients of this Lagrangian are then fixed by calculating scattering processes in both the relativistic and nonrelativistic theories.
A relativistic framework for dealing with particles of arbitrary spin is considered. In this framework the relevant terms in the scattering process are heavily constrained by the symmetries required of the electromagnetic current. This allows the determination of an effective Lagrangian valid for arbitrary spin. It is found that the only coefficients which depend upon the spin of the particle in question involve derivatives of the magnetic field. This general form is consistent with the previously derived Lagrangians for spin one-half and spin one particles.
With this effective nonrelativistic Lagrangian, the leading order binding and recoil corrections to the bound gyromagnetic ratio are calculated. These corrections are found to be universal, independent of the spin of the particles involved. This is understood as a consequence of the Bargmann-Michel-Telegdi equation.
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Jentschura, Ulrich D. [Verfasser]. "Quantum Electrodynamic Bound-State Calculations and Large-Order Perturbation Theory / Ulrich Jentschura." Aachen : Shaker, 2003. http://nbn-resolving.de/urn:nbn:de:101:1-2018123004421660355078.
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Singh, Asmita. "Illuminating the ultrafast excited state dynamics of protein-bound carotenoids in plants." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/63170.
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Global energy demands have escalated over the past few decades, creating a necessity for alternative energy sources. Solar technologies inspired by the primary solar energy storing process known on earth, photosynthesis, have subsequently gained popularity. The natural photosynthetic apparatus comprises a network of membrane-bound pigment-protein complexes, with the main plant light-harvesting complex (LHCII) consisting of chlorophyll (Chl) and carotenoid (Car) pigments. Electronic excitation energy transfer (ET) of the harvested energy takes place amongst these pigments on ultrafast timescales. This energy is funnelled towards a photosynthetic reaction centre where charge separation is achieved, creating a Biobattery, which powers the subsequent manufacture of energy-rich chemical compounds for photosynthetic activity. Transient absorption pump-probe spectroscopy has proven to be a useful technique for monitoring the evolution of the excited state dynamics, such as electronic transitions and excitation ET amongst Car and Chl pigments of LHCII trimers isolated from spinach leaves. This method was utilized to probe samples excited under four different conditions: at pump excitation wavelengths (𝜆𝑒𝑥) of 489 nm (preferentially exciting Cars Lutein1 and Neoxanthin) and 506 nm (targeting Cars Lutein2 and Violaxanthin), each with an intensity of either 800 nJ/pulse (relatively high) or 500 nJ/pulse (comparatively low). A global analysis was applied to each dataset using the robust, open-source Glotaran software, from which three kinetic decay lifetimes for the various processes were extracted. General spectral observations encompassed a negative pump ground state bleach (GSB) at each 𝜆𝑒𝑥; negative Chl b and Chl a GSBs, superimposed with negative stimulated emission (SE) signals; and a positive excited state absorption (ESA) band. The first lifetime of a few picoseconds corresponded mainly to Car-S2 depopulation, resulting either from energy relaxation towards Car-S1, or ET to Chls. Small, but distinct Chl b signals of less than 3 mOD were also detected on this timescale. The second lifetime, which is between 10 and 12 ps, was characteristic to the Lutein Car-S1 lifetime, mainly depicting Car-S1 ET to Chl a. The third lifetime, which extended from ~200 ps to the nanosecond timescale, was attributed to Chl a fluorescence. The 𝜆𝑒𝑥 of 489 nm directly excites the Chl Soret region, whilst excitation at 506 nm shows a pump intensity-dependence. Laser pulse photon density values were ~1014 photons·cm-2·pulse-1 for these datasets. Singlet-singlet annihilation calculations performed on the samples excited at 506 nm provided low annihilation probabilities of 9.0% and 11.5% for a low and high pump intensity, respectively, limiting the possibility of sample photobleaching. Optimization and redevelopment of the experimental setup significantly improved both the data quality and various recorded parameters, concluding that pump-probe spectroscopy was successful on the prepared LHCII trimers. Results acquired and calculations performed correlated with literature, where minimal changes were noticed in the timescales and ET pathways. The robustness of plant systems was confirmed through both excitation-wavelength and intensity dependence. This work paves the way for advanced studies on the role Cars play in non-photochemical quenching (NPQ), a self-protection mechanism of plants against over-illumination; and for the tailoring of artificial light-harvesting antennas based on research conducted on their natural counterparts.<br>Globale energievereistes het oor die afgelope paar dekades toegeneem, wat die ontwikkeling van alternatiewe energiebronne noodsaaklik maak. Sontegnologieë, geïnspireer deur die primêre sonenergiebergingsproses op aarde, fotosintese, het daarom gewild geword. Die natuurlike fotosintetiese apparaat bestaan uit 'n netwerk van membraangebonde pigment-proteïenkomplekse, met die hoof ligversamelingskompleks in plante (LHCII) wat bestaan uit chlorofil- (Chl) en karotenoïed- (Car) pigmente. Die energie wat deur die pigmente geabsorbeer word, word tussen elektroniese opgewekte toestande op verskillende pigmente op ultravinnige tydskale oorgedra. Hierdie energie word na ʼn fotosintetiese reaksiesentrum gekanaliseer, waar 'n ladingskeiding geïnduseer word en 'n Biobattery sodoende geskep word. Die energie wat in dié battery gestoor is, word gebruik om energieryke chemiese verbindings te vervaardig — wat as brandstof vir die plant dien om sy lewensfunksies te verrig. Tydopgeloste-absorpsie-pomp-tasting-spektroskopie is 'n nuttige tegniek om die dinamika tussen opgewekte toestande te volg. ‘n Voorbeeld van sulke dinamika is die elektroniese opwekking en energie-oordrag tussen die Car- en Chl-pigmente van geïsoleerde LHCII-trimere in spinasieblare. Hierdie metode is gebruik om monsters onder vier verskillende toestande te ondersoek by pompgolflengtes (𝜆𝑒𝑥) van 489 nm (waar hoofsaaklik die Cars Luteïne1 en Neoksantine opgewek word) en 506 nm (vir Cars Luteïne2 en Violaksantine), en pompenergieë van ‘n relatief hoë 800 nJ/puls, of 500 nJ/puls vir elke golflengte.<br>Dissertation (MSc)--University of Pretoria, 2017.<br>National Research Foundation (NRF)<br>Physics<br>MSc<br>Unrestricted
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Jones, Billy Darwin. "Light-front Hamiltonian approach to the bound-state problem in quantum electrodynamics /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487946103569513.
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Le, calvez Kévin. "Signatures of a 4pi periodic Andreev bound state in topological Josephson junctions." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAY099/document.
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Les isolants topologiques 3D sont un nouvel état de la matière décrit par un volume iso-lant électriquement et recouvert par des états de surface métalliques. Une jonction Joseph-son topologique (TJJ) formée autour de ces états de surface peut théoriquement contenirun mode lié d’Andreev ayant une périodicité doublée par rapport aux modes liés d’An-dreev conventionnels 2p périodiques. Le mode d’Andreev 4p périodique serait la briqueélémentaire de l’ordinateur quantique topologique. Ainsi, nous étudions la dynamique dece mode particulier lors de mesures de Shapiro sur des jonctions Josephson fabriquées surdes isolants topologiques à base de bismuth.A?n d’identi?er les e?ets d’un mode 4p-périodique dans une mesure de Shapiro, nousutilisons un model phénoménologique permettant de simuler la caractéristique courant-tension d’une TJJ lors de telles mesures. Nous prédisons deux signatures du mode 4p-périodique et estimons leur robustesse face aux e?ets de chau?age par e?et Joule et face àun modèle d’empoisonnement thermiquement activé du mode 4p-périodique.Par des mesures de Shapiro, nous étudions la dynamique des TJJ basées sur le matériausimple qu’est le Bi2Se3. L’observation des deux mêmes signatures précédemment anticipéespar nos simulations, à savoir un ordre d’apparition non conventionnel des pas de Shapiroainsi que la persistance d’un supercourant à la fermeture du plateau de Shapiro n = 0prouve la présence d’un mode 4p-périodique.Notre étude s’est également portée sur un autre isolant topologique le BiSbTeSe2. Nousavons e?ectué sa croissance par cristallisation liquide-solide et avons mis en évidence,par des mesures d’interférométrie supraconductrice une supraconductivité de surface sanstransport électronique par le volume<br>Three dimensional topological insulators (3D TI) are a new state of matter composedof an electrically insulating bulk covered by metallic surface states. Theoretically, a topo-logical Josephson junction composed of these surface states can host an Andreev Boundstate (ABS) that has twice the periodicity of the conventional 2p periodic ABSs. The4p periodic ABS is expected to be the building block of topological quantum computing.Therefore, we study the dynamic of this particular ABS by performing Shapiro measure-ment on Josephson junctions built with bismuth based 3D TI.To identify the e?ects of a 4p periodic ABS in a Shapiro measurement, we use a phe-nomenological model that simulates the voltage-current characteristics of a TJJ. We predicttwo signatures of the 4p periodic ABS and estimate their robustness against Joule heatingand thermally activated quasiparticle poisoning of the 4p periodic mode.We study the Josephson junctions dynamics by performing Shapiro measurements onjunctions built on Bi2Se3. We observe the two previously anticipated signatures, whichare the non-conventional appearance order of the Shapiro steps and the remaining of asupercurrent at the closing of the Shapiro step n = 0. They prove the presence of a 4pperiodic ABS.We also study the topological insulator BiSbTeSe2 that we have grown by using themelting growth method. By superconducting interferometric measurements, we show asuperconducting surface transport without bulk electronic conduction
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Jentschura, Ulrich D. [Verfasser]. "Quantum electrodynamic bound state calculations and large order perturbation theory / by Ulrich Jentschura." Aachen : Shaker, 2003. http://d-nb.info/968750435/34.
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Squires, Allison Holmes. "Engineering solid-state nanopores for detection of single transcription factors bound to DNA." Thesis, Boston University, 2014. https://hdl.handle.net/2144/19695.
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Thesis (Ph.D.)--Boston University<br>Detection and characterization of nucleic acid-protein interactions, particularly those involving DNA and transcription factors, remain significant barriers to our understanding of genetic regulation. Solid-state nanopores are extremely sensitive single molecule sensors with the capability to map local chemical and structural characteristics along the length of a biopolymer, providing label-free detection for a wide range of analyte lengths and sizes. Previous studies have utilized solid-state nanopores to detect complexes of DNA bound to many large proteins, but improvements to the sensing resolution of the nanopore platform are necessary for detection of single small transcription factors bound to DNA. This project encompasses two novel nanopore modifications that enhance output signal quality and time resolution in nanopores, and establishes solid-state nanopores as a platform for direct measurement of transcription factor-DNA complexes.
First, a novel fabrication process was developed to create locally thinned SiN membranes on a full-wafer scale. These modified nanopore chips provide several advantages over conventional solid-state nanopores, including improved signal-to-background ratio, higher probability of functionality, and clearly marked pore locations for re-imaging and array fabrication. Next, the volume outside the nanopore was modified by electrospinning a sparse, hydrophobic co-polymer nanofiber mesh (NFM) directly onto the nanopore chip. The NFM interacts with analyte molecules as they translocate through the pore, increasing residence time in the sensing volume and improving resolution by more than two orders ofmagnitude for a chemically optimized blend ofpoly(E-caprolactone) and poly(glycerol-co-E-caprolactone). Finally, modified nanopores were used for direct, label-free detection of single transcription factors bound to DNA. Translocations of these complexes reveal a combination oftwo possible sensing modalities; either the complex passes unhindered through the pore, causing a transient drop in current at the location ofthe bound protein, or the protein is unable to translocate and is removed as the DNA is electrophoretically driven through the nanopore. The DNA-binding domain of the transcription factor Early Growth Response Protein 1 (EGRl), known as zif268, is presented as a model system for this research. EGRl activates genes that control cell differentiation and mitogenesis, and participates in many regulatory processes including wound response, tumor suppression, and neuronal plasticity .
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Sturm, Sven [Verfasser]. "The g-factor of the electron bound in 28 Si 13+ : the most stringent test of bound-state quantum electrodynamics / Sven Sturm." Mainz : Universitätsbibliothek Mainz, 2012. http://d-nb.info/1022300652/34.
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Fazzini, Serena. "One dimensional extended Hubbard model: two-particle bound states and resonances." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7614/.
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In questo lavoro di tesi è stato svolto uno studio analitico sul modello di Hubbard esteso unidimensionale al fine di osservare la presenza di eventuali risonanze che possano dare origine alla formazione di stati legati di due particelle. L'esistenza di uno stato legato stabile ha suscitato grande interesse negli ultimi anni, sia in ambito teorico che sperimentale, poichè è alla base di molti fenomeni che vengono osservati nei sistemi a molti corpi a basse temperature, come il BCS-BEC crossover. Pertanto si è ritenuto utile studiare il problema a due corpi nel modello di Hubbard esteso, che in generale non è integrabile. Il modello considerato contiene interazioni a primi e secondi vicini, in aggiunta all'interazione di contatto presente nel modello di Hubbard.
Il problema è stato indagato analiticamente attraverso il Bethe ansatz, che consente di trovare tutti gli autovalori e le autofunzioni dell'Hamiltoniana. L'ansatz di Bethe sulla funzione d'onda è stato generalizzato per poter tener conto dei termini di interazione a più lungo raggio rispetto all'interazione di contatto.
Si trova che, in questo modello, nel limite termodinamico, possono avvenire delle risonanze (o quasi-risonanze) in cui la lunghezza di scattering diverge, contrariamente a quanto avviene nel modello di Hubbard. Tale fenomeno si verifica quando il livello energetico discreto degli stati legati “tocca” la banda di scattering. Inoltre, con l'aggiunta di nuovi termini di interazione emergono nuovi stati legati. Nel caso in esame, si osservano due famiglie di stati legati, se lo spin totale delle due particelle è 1, e tre famiglie di stati legati, se lo spin totale è 0.
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Borzov, Dmitry. "Renormalization approach to bound state energy computation for two ultracold atoms in an optical lattice." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/39749.
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In experiments with ultra-cold gases, two alkali atoms, that interact with repulsive or attractive potentials and are confined to an optical lattice, can form bound states. In order to compute the energy of such states formed by atoms in the lowest Bloch band, one needs to take into account the intra-band corrections arising from contributions by higher Bloch bands. As it is hard to implement, known calculations tend to neglect them altogether thus setting up a limit for the precision of such computations.
To address the problem we apply an approach that uses renormalization-group equations for an effective potential we introduce.
It allows for the expression of the bound state energy in terms of the free-space interaction scattering length and parameters of confining potentials.
Expressions for bound state energies in 1D, 2D and 3D optical lattices are reported.
We show that the method we use can be easily tailored to various cases of atoms confined by external fields of other geometries. A known result for atoms confined to a quasi-2D system is reproduced as an example. Universality of the approach makes it a useful tool for such class of problems.
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Manolopoulos, David Eusthatios. "Close-coupled equations : the log derivative approach to inelastic scattering, bound state and photofragmentation problems." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254402.
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Uusitalo, P. (Pauliina). "The bound states in the quantum waveguides of shape Y, Z, and C." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526217017.
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Abstract In this thesis, we study quantum waveguides and their spectral properties. A quantum waveguide is a system of narrow strips or tubes. That is, the waveguide has large longitudinal but small transverse sizes. The study of quantum waveguides is essential in the semi-conductor industry, and the waveguides are used to model the electron behavior in these devices. We consider two- and three-dimensional waveguides with sharp bends and question whether the quantum particle can propagate in the waveguide. It is well known that a certain type of bends and bulges cause the resonance phenomena, that is, at some energy levels the electron motion is localized in a finite area, and the propagation is disturbed. The study of waveguides leads to the interesting field of mathematics - the spectral analysis of differential operators. For a waveguide having high purity and a crystalline structure, the electron motion can be considered as a free particle motion with effective mass. This gives rise to the spectral problem, that is, the eigenvalue problem of the Laplace operator. On the boundary we set the Dirichlet conditions. This thesis consists of three parts and in each part we study waveguides which form sharp bends in the junctions where two or three outlets are joined together. To be precise, we consider waveguides which resemble the letters Y, Z, and C. We study the discrete spectrum corresponding to these waveguides and the behavior of the bound modes when the geometry is slightly changed. For this, we apply the variational, numerical, and asymptotic methods. For the Y-shaped waveguide, we let one outlet become wider than the others and found that a critical width exists, so that for smaller width values, exactly one bound state exists, but for larger values, no bound modes exist. We also let the angle between the strips to vary and found that the number of the bound modes highly depends on the opening angle of the outlets in the Y-shaped waveguide. For the Z- and C-shaped waveguides, we let the height of the waveguide change. We saw that there may appear two bound states at most. Moreover, for the C-shaped waveguide, the first is monotone increasing as a function of height and the second eigenvalue is monotone decreasing. For the Z-shaped waveguide, we show that the lowest eigenvalue as a function of the height is not monotone<br>Tiivistelmä Tässä väitöskirjassa tutkitaan kvanttiaaltojohteisiin liittyvää ominaisarvo-ongelmaa. Kvanttiaaltojohteessa aallon eteneminen on rajoitettu tiettyyn suuntaan, ja johde on poikittaissuunnassa nanokokoluokkaa. Kvanttiaaltojohteiden tutkimus on tärkeä osa nykyistä puolijohdeteknologiaa. Tutkimuksessamme olemme keskittyneet kaksi- ja kolmiulotteisiin aaltojohteisiin, jotka geometrialtaan muistuttavat Y-, Z- tai C-kirjainta. Haluamme tietää millaisissa tilanteissa elektronin liike aaltojohteessa estyy. Yleisesti tiedetään, että aaltojohteessa olevat pullistumat ja mutkat johtavat niin sanottuun sidottuun tilaan, ts. tilanteeseen että tietyllä taajuudella tai energiatasolla oleva partikkeli jää lokalisoituun tilaan. Aaltojohde rakentuu puhtaasta kiderakennemateriaalista, joka on kokoluokaltaan pieni poikittaissuunnassa, niin että elektronin liikettä voidaan kuvata vapaan elektronin mallilla Schrödingerin yhtälössä, jossa elektronilla on effektiivinen massa. Tämä johtaa Laplace-operaattorin ominaisarvo-ongelmaan, reunaehtoina on aaltojohteille käytetty Dirichlet nollareuna-arvoja. Tässä väitöstutkimuksessa on tutkittu kolmea erityyppistä aaltojohdetta, joiden geometriaa voidaan kuvata kirjainten Y, C ja Z avulla. Jokaisessa tapauksessa on tutkittu spektristä erityisesti diskreettiä osaa, ja erityisesti mahdollisia muutoksia diskreetissä spektrissä geometristen parametrien muuttuessa. Diskreetin spektrin tutkimiseen on käytetty variaatiomenetelmiä, asymptoottista analyysiä sekä numeerisista menetelmistä elementtimenetelmää. Geometrialtaan kirjainta Y muistuttava aaltojohde koostuu kolmesta haarasta, joista yhden leveyden annetaan varioida. Tällöin voidaan löytää kriittinen raja, siten että jalan leveyden ollessa tätä rajaa pienempi on diskreetti spektri epätyhjä kun taas leveyden ollessa kriittistä rajaa suurempi, diskreetti spektri on tyhjä. Toisessa tapauksessa jalan leveydet pidetään samana, mutta annetaan kulman kahden haaran välillä muuttua. Voidaan nähdä, että diskreetissä spektrissä olevien ominaisarvojen lukumäärä riippuu aaltojohteen kulmasta siten että mitä pienempi kulma kahden haaran välillä, sitä enemmän ominaisarvoja on diskreetissä spektrissä. Vastaavasti Z- ja C- aaltojohteissa, aaltojohteen korkeutta säädellään. Havaitaan, että korkeuden kasvaessa, voi aaltojohteessa esiintyä korkeintaan kaksi ominaisarvoa diskreetissä spektrissä. Lisäksi C-aaltojohteen ensimmäisen ominaisarvon voidaan havaita olevan kasvava aaltojohteen korkeuden funktiona kun taas toinen ominaisarvoista on vähenevä. Toisaalta taas Z-aaltojohteen pienin ominaisarvo korkeuden funktiona ei ole monotoninen
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Middleton, Dewayne. "A survey of Upward Bound Programs on the achievement of rural high school students." Diss., Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-06232008-120222.
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Wort, Philip M. (Philip Michael) Carleton University Dissertation Physics. "Two Fermion bound state equation using light front Tamm-Dancoff field theory in 3+1 dimensions." Ottawa, 1992.
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Tsibidis, George D. "The Breit equation and its application to bound state problems for long-range and short-range interactions." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390131.
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A non-covariant but approximately relativistic two-body wave equation describing the quantum mechanics of two fermions interacting with one another through a potential containing scalar, pseudoscalar and vector parts is presented. It is based on a generalisation of the equation introduced by Breit in 1929. After expressing the sixteen component twobody wavefunction in terms of a radial and an angular function by means of the multi pole expansion, the initial equation can be reduced into a set of sixteen radial equations which, in turn, can be classified in accordance to the parity and the state of the wavefunctions involved. The adequacy of the reduced equations in describing real problems is discussed, first, by applying the theory to a QED problem, the calculation of the lowest bound states, 1So and 351, of positronium to order 0'4. Second, the knowledge of the bottomium and charrnoniurn spectra serves as a laboratory to test both the efficiency of the potential which is supposed to represent the interaction between two quarks leading to the formation of mesons, and the reliability of the Breit equation. The final results are presented in such a form as to allow a direct comparison with both experimental data and existing theories. Results are, also, obtained for a stronger Coulomb-like vector potential as well as for a scalar square well potential. The former case is applied to a bound state of a monopoleantimonopole system.
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Robison, Kaitlyn. "Motherhood Bound by State Supervision: An Exploratory Study of the Experiences of Mothers on Parole and Probation." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5116.
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With an influx of women entering the incarcerated population comes an increase in the number of children who have a mother serving time. As these mothers are released from prison or jail they immediately enter into the parole or probation system. This research focuses on the experiences of these women within state supervision, but also on what it means to be a mother. Through thematic analysis of 8 in-depth interviews with women who are currently on or were recently released from probation or parole, this study explores how women manage the combined identity of "mother under state supervision." There are many instances of direct conflict that result from the combined identity of "mother under state supervision." In order to deal with this conflict and manage their combined identity, the women use a multitude of tools. This analysis focuses on three of those tools: social support, managing openness, and redefining ways to be good moms. What has emerged from this analysis is the complex nature of navigating the combined identity of "mother under state supervision" and the tools that this particular group of women have used to do so.
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López, José G. "Theoretical studies of the dynamics and spectroscopy of weakly bound systems." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1127220592.
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Boutin, David. "First direct observation of bound-state beta-decay measurements of branching and lifetime of 207 Tl 81+ fragments /." Darmstadt : GSI, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?idn=978036662.
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Higgins, Nicholas Daniel. "The Homeward Bound-Ness of Crimean Tatars: A Clash of National Identity, the State, and the Crimean Peninsula." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1578921172575651.
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Tomida, Natsuki. "Search for η’-nucleus bound states from ¹²C(γ, p) reaction with simultaneous detection of decay products". Kyoto University, 2020. http://hdl.handle.net/2433/258972.
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Kratz, Jonathan L. "Robust Control of Uncertain Input-Delayed Sample Data Systems through Optimization of a Robustness Bound." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429149093.
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Popham, Jennifer Mei-An. "A solid state NMR dipolar recoupling study of surface interactions of a N-terminal statherin fragment bound to hydroxyapatite /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/8517.
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Tokiyasu(Okamura), Atsushi. "Search for the K-pp bound state using the d(γ,K+π-)X reaction at Eγ=1.5-2.4 GeV". 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188483.
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Frolov, Alexei M. "Quantum-mechanical study of few-body systems, a variational study of bound state spectra in three- and four-body systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0005/NQ38308.pdf.
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Shaw, Wendy Jane. "Determination of the structure and dynamics of salivary statherin and N-terminal fragments bound to hydroxyapatite using solid state NMR /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/8624.
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Marwah, Gaurav. "Algorithms for stochastic finite memory control of partially observable systems." Master's thesis, Mississippi State : Mississippi State University, 2005. http://library.msstate.edu/etd/show.asp?etd=etd-07082005-132056.
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Cornish, Simon Lee. "A solid state laser system for high resolution spectroscopy of the 1S-2S transition in muonium." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297937.
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Sidhu, Ragandeep Singh [Verfasser], and Yuri A. [Akademischer Betreuer] Litvinov. "Measurement of the bound-state beta decay of bare 205Tl81+ ions at the ESR / Ragandeep Singh Sidhu ; Betreuer: Yuri A. Litvinov." Heidelberg : Universitätsbibliothek Heidelberg, 2021. http://d-nb.info/1238076491/34.
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Amselem, Elias. "Dynamics of Quantum Correlations with Photons : Experiments on bound entanglement and contextuality for application in quantum information." Doctoral thesis, Stockholms universitet, Fysikum, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-66469.
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The rapidly developing interdisciplinary field of quantum information, which merges quantum and information science, studies non-classical aspects of quantum systems. These studies are motivated by the promise that the non-classicality can be used to solve tasks more efficiently than classical methods would allow. In many quantum informational studies, non-classical behaviour is attributed to the notion of entanglement. In this thesis we use photons to experimentally investigate fundamental questions such as: What happens to the entanglement in a system when it is affected by noise? In our study of noisy entanglement we pursue the challenging task of creating bound entanglement. Bound entangled states are created through an irreversible process that requires entanglement. Once in the bound regime, entanglement cannot be distilled out through local operations assisted by classical communication. We show that it is possible to experimentally produce four-photon bound entangled states and that a violation of a Bell inequality can be achieved. Moreover, we demonstrate an entanglement-unlocking protocol by relaxing the condition of local operations. We also explore the non-classical nature of quantum mechanics in several single-photon experiments. In these experiments, we show the violation of various inequalities that were derived under the assumption of non-contextuality. Using qutrits we construct and demonstrate the simplest possible test that offers a discrepancy between classical and quantum theory. Furthermore, we perform an experiment in the spirit of the Kochen-Specker theorem to illustrate the state-independence of this theorem. Here, we investigate whether or not measurement outcomes exhibit fully contextual correlations. That is, no part of the correlations can be attributed to the non-contextual theory. Our results show that only a small part of the experimental generated correlations are amenable to a non-contextual interpretation.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 5: Submitted. Paper 6: Submitted.</p>
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Alzate, Oscar. "Structural and functional studies on the Bacillus Thuringiensis Cry1Ab (delta)-endotoxin and its membrane bound state to Manduca Sexta brush border membrane vesicles /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487952208108499.
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Batista, Alex de Moura. "Sobre um Sistema do tipo Schrödinger-Poisson." Universidade Federal da Paraíba, 2012. http://tede.biblioteca.ufpb.br:8080/handle/tede/7369.
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Previous issue date: 2012-04-26<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>In this dissertation, we study the existence of two types of non-negative weak solutions
for a class of problems of Schrodinger-Poisson type. This kind of problem models, for
example, several physical phenomena in quantum mechanics. Initially, by minimization
arguments, Splitting Lemma and the Variational Principle of Ekeland we find a weak
solution that minimizes the minimum energy level associated to the variety of Nehari
N. This is the so-called ground state solution. Afterwards we will find, by using the
Linking Theorem, a strictly positive weak solution which is not a ground state solution:
the so-called bound state solution.<br>Nesta dissertação, estudaremos a existência de dois tipos de soluções fracas não
negativas para uma classe de problemas do tipo Schrödinger-Poisson, os quais modelam
fenômenos físicos, por exemplo, em Mecânica Quântica. Inicialmente, encontraremos
através de argumentos de minimização, do Lema Splitting e do Princípio Variacional de
Ekeland, uma solução fraca que minimiza o nível de energia mínima associado a variedade
de Nehari N. Tal solução é denominada do tipo ground state. Em seguida, encontraremos
através do Teorema de Linking, uma solução fraca estritamente positiva que não é do tipo
ground state. Tal solução é denominada do tipo bound state.
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Blanckenberg, Jacobus Petrus. "Skyrme model description of heavy baryons with strangeness." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96953.
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Boutin, David [Verfasser]. "First direct observation of bound-state beta-decay : measurements of branching and lifetime of 207Tl81+ fragments / Gesellschaft für Schwerionenforschung mbH, Darmstadt. Vorgelegt von David Boutin." Darmstadt : GSI, 2005. http://d-nb.info/978036662/34.
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Ichikawa, Yudai. "Strange dibaryon system produced in the d(π+, K+) reaction at J-PARC". 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199096.
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Cordero, Raymundo. "Limit state analysis : adaptive finite element upper and lower bound approach to the evaluation of the limit load of a Von Mises rigid-plastic material body in plane stress." Thesis, Swansea University, 2005. https://cronfa.swan.ac.uk/Record/cronfa42326.
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A new approach to the computation of the Limit load of a Von Mises rigid-plastic material structure modelled in plane stress is assessed. Most international design codes require the engineer to establish the safety of a structure for a given set of design loads under the so-called limit state conditions. The limit state represents the failure point at which the structure begins to exhibit unbounded deformations. Under limit state conditions, the deformation of the solids tend to concentrate on thin failure bands, known as slip-lines. This makes the finite element analysis a challenging task as the mesh needs to be adapted to capture these bands accurately. In order to achieve this, an adaptive technique is required whereby the error produced in each finite element is measured and if required the element is subdivided automatically. In order to measure this error both an upper and lower bound of the exact solution need to be evaluated. In this thesis, a novel technology to obtain the lower bound is derived and implemented together with mesh adaptivity technology. A lower bound is found from a state of stresses in equilibrium with the external forces. The proposed technique obtains such equilibrated state using the stresses obtained during the upper bound evaluation. These stresses, although not strictly in equilibrium, can be balanced using procedures available in the literature. The present aim of the research project is to develop numerical technology based on the finite element method to calculate the limit state of two-dimensional solids in plane stress. The upper bound theorem of limit analysis is implemented by means of a Lagrangian optimization technique solved by the Newton-Raphson method with Line Search. A control parameter to deal with the singularity of the tangent stiffness matrix due to the yielding condition is used along the range of admissible rate of deformations for a rigid-plastic material. The lower bound theorem is then applied by performing a technique to equilibrate the interelement tractions, kinematically solving a sequence of local problems using the equilibrated tractions as an updated load input, which lets us determine the elementwise contribution to both the upper and lower bounds. An adaptive technique is then implemented, based on the elemental contributions to the difference between the upper bound and the lower bound of the collapse multiplier. Both non-adaptive and adaptive results are evaluated. Results show a good performance of the solution technique, both in comparison with well known plane stress bound values and also in the graphical output obtained in the form of refined regions which describe the occurrence of slip-line patterns and/or localized yielding regions.
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Kaladzhyan, Vardan. "Spin polarisation and topological properties of Yu-Shiba-Rusinov states." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC215/document.
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Dans ce manuscrit de thèse, nous revisitons d'abord la physique des états de Yu-Shiba-Rusinov, en nous concentrant sur leur polarisation en spin. Nous commençons par montrer théoriquement que nous pouvons extraire beaucoup d'informations sur le supraconducteur hôte, en analysant la densité locale d'états électroniques liée à la présence d'impuretés magnétiques. Tout d'abord, nous démontrons que le couplage spin-orbite peut être lu directement et sans ambiguïté par la spectroscopie par effet tunnel résolu en spin dans les systèmes bidimensionnels et unidimensionnels, qu’ils soient supraconducteurs ou métalliques. Nous analysons les oscillations induites par les impuretés dans la densité d'états électroniques. En particulier, nous nous concentrons sur la transformation de Fourier (TF) des oscillations de Friedel et nous notons que les caractéristiques à haute intensité apparaissent pour un vecteur d'onde donné par deux fois la longueur inverse du spin-orbite. Ensuite, nous montrons qu'il est possible de déterminer le mécanisme d’appariement dominant, qu’il soit en ondes s ou en ondes p, dans les supraconducteurs non conventionnels en analysant la structure spectrale résolue en spin des états liés de Yu-Shiba-Rusinov. De manière frappante, nous démontrons qu'une analyse minutieuse de la densité d'états électroniques polarisée en spin ne permet pas seulement de caractériser sans équivoque le degré d’appariement de type triplet, mais également son orientation, a.k.a. le vecteur d. Enfin, nous proposons et discutons deux approches différentes d'ingénierie et de contrôle des phases topologiques à l’aide d’impuretés scalaires et magnétiques. Nous commençons par fournir une théorie microscopique des réseaux d'impuretés scalaires sur les supraconducteurs chiraux. Nous montrons que pour un supraconducteur topologique de type chiral, les impuretés scalaires donnent lieu à une hiérarchie complexe de phases non triviales distinctes avec des nombres de Chern élevés. Deuxièmement, nous proposons et étudions théoriquement une nouvelle plate-forme prometteuse que nous appelons «la chaîne dynamique de Shiba», c'est-à-dire une chaîne d'impuretés magnétiques classiques dans un supraconducteur en ondes s avec des spins qui précessent. Nous montrons que cette approche peut être utilisée non seulement pour créer une phase supraconductrice topologique, mais surtout pour contrôler les transitions de phase topologiques au moyen de la dynamique de la texture de la magnétisation. Ce manuscrit est organisé comme suit. Dans la première partie, les informations d'introduction essentielles sur la supraconductivité, les oscillations de Friedel et les états de Yu-Shiba-Rusinov sont fournies. La deuxième partie est consacrée à la polarisation en spin des états Yu-Shiba-Rusinov et aux propriétés qui pourraient être extraites au moyen de la microscopie par effet tunnel résolu en spin. Dans la dernière partie, deux configurations proposées pour l'ingénierie de phases topologiques, basées sur les états induits par les impuretés, sont présentées, suivies de conclusions, d’un bref résumé des réalisations de cette thèse et enfin d’une discussion de possibles directions futures<br>In this manuscript we first revisit the physics of Yu-Shiba-Rusinov subgap states, focusing on their spin polarisation. We start by showing theoretically that we can extract a considerable amount of information about the host superconductor, by analysing spin-polarised local density of states related to the presence of magnetic impurities. First, we demonstrate that the spin-orbit coupling in two-dimensional and one-dimensional systems, both superconducting and metallic, can be read-off directly and unambiguously via spin-resolved STM. We analyse the impurity-induced oscillations in the local density of states. In particular, we focus on the Fourier transform (FT) of the Friedel oscillations and we note that high-intensity FT features appear at a wave vector given by twice the inverse spin-orbit length. Second, in unconventional superconductors with both s-wave and p-wave pairing, by analysing the spin-resolved spectral structure of the Yu-Shiba-Rusinov states it is possible to determine the dominating pairing mechanism. Most strikingly, we demonstrate that a careful analysis of spin-polarised density of states allows not only to unambiguously characterise the degree of triplet pairing, but also to define the orientation of the triplet pairing vector, also known as the d-vector.Finally, we discuss two different ways of engineering and controlling topological phases with both scalar and magnetic impurities. We start with providing a microscopic theory of scalar impurity structures on chiral superconductors. We show that given a non-trivial chiral superconductor, the scalar impurities give rise to a complex hierarchy of distinct non-trivial phases with high Chern numbers. Second, we propose and study theoretically a new promising platform that we call 'dynamical Shiba chain', i.e. a chain of classical magnetic impurities in an s-wave superconductor with precessing spins. We have shown that it can be employed not only for engineering a topological superconducting phase, but most remarkably for controlling topological phase transitions by means of magnetisation texture dynamics.This manuscript is organised as follows. In the first part, the essential introductory information on superconductivity, Friedel oscillations and Yu-Shiba-Rusinov states is provided. The second part is dedicated to spin polarisation of Yu-Shiba-Rusinov states and the properties that could be extracted by means of spin-resolved STM measurements. In the last part, two setups proposed for topological phase engineering based on impurity-induced states are presented, followed by conclusions with a brief summary of the thesis achievements and further directions to pursue
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Münzer, Robert Helmut [Verfasser], Laura [Akademischer Betreuer] Fabbietti та Peter [Akademischer Betreuer] Fierlinger. "Search for the kaonic bound state ppK- : Exclusive analysis of the reaction p + p → p + K+ + Λ at the FOPI experiment at GSI / Robert Helmut Münzer. Gutachter: Peter Fierlinger ; Laura Fabbietti. Betreuer: Laura Fabbietti". München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1051496985/34.
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Yu, Terri M. (Terri Mak) 1981. "Bounds on the entanglability of thermal states in liquid-state nuclear magnetic resonance." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/18023.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.<br>Includes bibliographical references (p. 235-243).<br>Theorists have recently shown that the states used in current nuclear magnetic resonance (NMIR) quantum computing experiments are not entangled. Yet it is widely believed that entanglement is a necessary resource in the implementation of quantum algorithms. The apparent contradiction might be resolved by the experimental realization of an entangled NMR state. Designing such an experiment requires us to know whether or not the initial NMR state is entanglable--that is, does there exist a unitary transform that entangles the state? This computational and theoretical thesis explores the entanglability of thermal states in N-[alpha] space where N specifies the number of qubits and [alpha] characterizes the polarization of the thermal state. The thermal state is transformed by the Bell unitary U[sub]b,s and the entanglement of the transformed state is measured by negativity. Here we present numerically generated negativity maps of N-[alpha] space (N [less than or equal to] 12) and explicit negativity formulas for U[sub]b,s-transformed thermal states. We also give a general method that uses the symmetry of a special mixed Bell state family to derive bounds on the entanglement of generic Bell-transformed thermal states. This approach yields analytical bounds on the entanglability of thermal states and gives an upper limit of N [less than or equal to] 20, 054 required to entangle a thermal state under ideal experimental conditions.<br>by Terri M. Yu.<br>M.Eng.
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Foster, David John. "Soliton interactions and bound states." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/467/.
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The research presented in this thesis is concerned with soliton interactions and bound states. We consider a on-topological soliton in (1 + 1) dimensions and topological models in (2 + 1) and (3 + 1) dimensions. In chapter 2 we consider Qballs, which are non-topological solitons, in (1 + 1) dimensions. Here we note the semi-integrable behaviour of small-charge Qballs. This leads us to propose a possible mechanism to explain the two distinct oscillatory modes of a Qball breather. In chapter 3 we are interested in the (2+1)-dimensional baby-skyrme model, which is a lower-dimensional analogue of the Skyrme theory. We discover new chain-like bound-state minimum-energy solutions. We then analyse whether these solutions are the minimum-energy solutions on a cylinder, and then finally on the torus. In chapter 4 we discuss a new (2 + 1)-dimensional model containing a baby skyrmion coupled to a vector meson. This is an analogue of the (3 + 1)-dimensional Skyrme theory containing a vector meson. We use this lower-dimensional analogue to numerically justify the use of a rational map ansatz in the analysis of the (3 + 1)-dimensional skyrmion. Also we analytically prove why the baby-skyrme model, and the model containing a baby skyrmion stabilised by a vector meson, have very similar solutions. Chapter 5 discusses Hopf solitons. Instead of being lumps, Hopf solitons actually resemble loops of string. Their charge is related to the string's knotting and twisting. In this chapter we include an extra mass term in the Skyrme-Faddeev theory; this gives solitons which are exponentially localised. We then explore the infinite-coupling case, which gives compact Hopons. This chapter is part of an ongoing investigation. All of the original research results presented are my own results.
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Howe, Kiel. "MAN TOP QUARK STATES BOUND BY HIGGS INTERACTION: Relativistic bound states and dynamical electroweak symmetry restoration." Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/192484.
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Wright, Nicholas J. "Bound states of Van der Waals trimers." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/5048/.
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A method for calculating the energy levels and wave functions of floppy tri- atomic systems such as rare-gas trimers has been developed. It is based upon a potential-optimized discrete variable representation and takes into account the wide-amplitude vibrations that occur in such systems. The quadrature error that occurs in DVR calculations is analysed and a method of correction implemented. The diagonalisation procedure is based upon a combination of successive diagonalisation and truncation and a Lanczos diagonaliser. Using this method the wave functions of the Ar(_3) Van der Waals trimer have been calculated. The wave functions for the low-lying states show very regular behaviour. Above the barrier to linearity, most of the wave functions are irregular but some have simple nodal patterns that suggest localization along periodic orbits. In addition to the "horseshoe" states previously described for H(^+)(_3), localized features corresponding to symmetric and antisym metric stretching vibrations around a linear configuration have been identified. The different localized modes can be combined to form more complex states in a manner analogous to normal modes. A preliminary study of the rotational states of Ar(_3) has also been performed. The rotational constants for the low lying states of Ar(_3) reflect the increasing average size of Ar(_3) with increasing vibrational excitation. The rotational constants are obtained from two methods, expectation values and energy level differences. The results for the levels above the barrier to isomerisation reveal that the simple models used for obtaining the rotational constants are no longer valid and indicate that a more sophisticated treatment is necessary.
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Baldo, Mesa Casa Lucas. "Majorana bound states in Rashba nanowire junctions." Thesis, Uppsala universitet, Materialteori, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-416237.
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Nanowires with Rashba spin-orbit coupling represent a promising platform for the realization of one-dimensional topological superconductivity and Majorana bound states. In this work we investigate Majorana bound states in hybrid normal-superconductor and short superconductor-normal-superconductor junctions based on nanowires with Rashba spin-orbit coupling. In particular, we explore consequences of the topological phase transition as well as the non-locality and self conjugation properties of the Majorana states on the low-energy spectrum and the Josephson effect in the case of superconductor-normal-superconductor junctions. Our work shows the great potential of hybrid junctions as a platform for the study of topological superconductivity and Majorana bound states.
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Brisudova, Martina Maria. "QCD bound states in light-front Hamiltonian approach /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487942739806751.
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Baggott, Rory. "Modifications of bound states in dense plasma environments." Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/90134/.
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Electronic bound states in dense plasmas are modified, due to screening of ionic potentials by nearby free charge carriers. In particular, screening typically reduces the ionization energies of bound electrons. In this thesis, we explore the key physics underlying bound state modifications and ionization energies in dense plasmas. A theoretical framework is developed to study the free electrons and ion structure, and to calculate the resulting electrostatic fields in the plasma. The influence of such external fields on electronic bound states is then calculated. The framework is extended to include nonequilibrium plasmas, with populations of high-energy electrons. The screened potential around a central test ion is studied using the nonlinear Poisson equation. This approach allows different treatments for the free electrons, ions and the potential due to the central test ion to be evaluated. Quantum mechanical interactions between the bound and free electrons are found to be important in determining the screened potential, as are correlations between ions. The modified bound states are then calculated using a Hartree-Fock method, which takes into account the finite extent of bound state wavefunctions. The relationship between the modification of bound states and the modelling of x-ray scattering is also explored. We show how the modified bound state energies could be obtained from quantities that can be determined from x-ray Thomson scattering experiments. The nonlinear model is applied to an analysis of recent experiments on compressed plastics; on compressed and solid-density aluminium; and on shocked iron. These experiments had provided seemingly contradictory evidence regarding the applicability of existing screening models. The nonlinear screening model is found to partly reconcile this apparent contradiction. A screening model suitable for the treatment of nonequilibrium systems is applied to a model distribution function. The resulting ionization energies are found to be insensitive to the shape of the high-energy part of the distribution function. However, the role of hot electrons as an energy sink is found to be important in modelling screening in nonequilibrium systems. The presence of hot electrons reduces the bulk temperature relative to an equilibrium system, resulting in stronger screening overall.