We demonstrate experimentally that the multiphoton ionization rate in gallium arsenide depends on the alignment of the laser polarization with respect to the crystal axis. We show real-time modulation of 1900nm laser ionization rate, through viewing transmission, which mimics the symmetry of the semiconductor crystal. We propose that the modulation in the ionization rate arises because the varying reduced effective carrier mass, as predicted by Keldysh theory. We show direct comparison of the experimental transmission modulation depth with that predicted by Keldysh theory. This opens up a novel method for real-time non-invasive crystallography of crystalline materials.

We present a detailed strong lensing (SL) mass reconstruction of the core of the galaxy cluster MACS J2129.4-0741 (z(cl) = 0.589) obtained by combining high-resolution Hubble Space Telescope photometry from the CLASH (Cluster Lensing And Supernovae survey with Hubble) survey with new spectroscopic observations from the CLASH-VLT (Very Large Telescope) survey. A background bright red passive galaxy at z(sp) = 1.36, sextuply lensed in the cluster core, has four radial lensed images located over the three central cluster members. Further 19 background lensed galaxies are spectroscopically confirmed by our VLT survey, including 3 additional multiple systems. A total of 31 multiple images are used in the lensing analysis. This allows us to trace with high precision the total mass profile of the cluster in its very inner region (R < 100 kpc). Our final lensing mass model reproduces the multiple images systems identified in the cluster core with high accuracy of 0.4 arcsec. This translates to a high-precision mass reconstruction of MACS 2129, which is constrained at a level of 2 per cent. The cluster has Einstein parameter Theta(E) = (29 +/- 4) arcsec and a projected total mass of M-tot (< Theta(E)) = (1.35 +/- 0.03) x 10(14) M-circle dot within such radius. Together with the cluster mass profile, we provide here also the complete spectroscopic data set for the cluster members and lensed images measured with VLT/Visible Multi-Object Spectrograph within the CLASH-VLT survey.

This work is focused on a search for strong gravitational lenses in early-type galaxies (ETGs). The total number of samples is 4,706 galaxies encompassing a magnitude range 15.0 < i < 18.0 and colour 3.5 < (u-r) < 5.0. Two databases were employed as the source of K-band images (UKIDSS Large Area Survey) and g, r, i images (SDSS). All samples were fitted to a Sersic component and automatically processed using GALFIT (Peng et al. 2002; Peng et al. 2010) inside a Python script (Appendix A). The first classification generated 259 galaxies which are seen as single galaxies in their K-band images. These galaxies were then reclassified based on image contouring in g, r, i, and K filters and therefore resulted in three categories of samples: Sample A (99 galaxies), Sample B (96 galaxies), and Sample C (64 galaxies).

In the study of Banach spaces, the development of some key properties require studying topologies on the collection of closed convex subsets of the space. The subcollection of closed linear subspaces is studied under the relative slice topology, as well as a class of topologies similar thereto. It is shown that the collection of closed linear subspaces under the slice topology is homeomorphic to the collection of their respective intersections with the closed unit ball, under the natural mapping. It is further shown that this collection under any topology in the aforementioned class of similar topologies is a strong Choquet space. Finally, a collection of category results are developed since strong Choquet spaces are also Baire spaces.

Atteindre le régime de couplage fort entre des nanocavités et des systèmes atomiques est un élément clé dans l'information quantique. Durant ma thèse, j'ai designé et fabriqué des nanocavités à cristal photonique en GaInP pour le couplage fort autour de 800 nm, longueur d'onde typique des atomes du Rubidium (780 nm) et de Césium (852 nm), les plus utilisés dans le domaine, ainsi que de l'Argon (811 nm). L'objectif est de faire interagir ces atomes avec la partie évanescente du mode fondamental de la nanocavité. Pour cela, un facteur de qualité de l'ordre de 8.10^4 et un volume modal inférieur à 0,04 µm^3 est nécessaire.La nanocavité est l'élément clé d'une plateforme nanophotonique. Nos plateformes sont composées d'une nanocavité à cristal photonique résonant autour de 800 nm, d'un réseau-coupleur pour collecter la lumière issue d'une fibre optique et vice versa et de guides d'alimentation pour transporter la lumière du réseau-coupleur à la nanocavité. Plusieurs défis technologiques ont émergé. La nanocavité doit avoir un fort facteur de qualité et un faible volume modal, le réseau-coupleur doit collecter le maximum de lumière issue de la fibre, les guides d'alimentation doivent transporter la lumière sans perte et, enfin, un mécanisme pour coupler la lumière des guides d'alimentation dans la nanocavité devait être trouvé.J'ai simulé, designé, fabriqué et caractérisé les éléments de ma structure. J'ai obtenu des facteurs de qualité supérieurs à 10^7 en théorie, et de l'ordre de 2.10^4 expérimentalement, détenant ainsi le record pour les cavités en GaInP autour de la longueur d'onde de 800 nm pavant la voie à la réalisation des expériences de couplage fort. / Reaching the strong coupling between nanocavities and atomic systems is a key element for Quantum Information. During my PhD, I designed and fabricated photonic crystal nanocavities in Gallium Indium Phosphide (GaInP)for strong coupling around 800,nm, typical wavelength of atoms such as Rubidium (780,nm), Cesium (852 nm), the most used in this domain, and the Argon atoms (811 nm).The aim of my PhD thesis is to provide with a nanophotonic platform dedicated to strong coupling interaction. For this, nanocavities having optical resonances arounf 800 nm, with quality factors larger than 8.10^4 and mode volumes smaller than 0.04µm^3 are necessary.The nanocavity is a key element of nanophotonic plateform. Our platforms are composed of a photonic crystal nanocavityitself, a grating-coupler in order to collect light from a optic fiber and vice versa and feeding waveguides in order to transport the light from the grating-coupler to the cavity. An efficient nanophtonic platfom for a reaslitic implementation should have a nanocavity with a large Q-factor and small mode volume. The grating-coupler must efficiently collect the light from the optical fiber, and the feeding waveguides must transport the light without losses.I simulated, designed,fabricated and caracterized the elements of my structure. I obtained quality factors larger than 10^7 in theory, and about 2.10^4 experimentally, getting the record for the nanocavities in GaInP around the wavelength 800 nm, which make them close to realize experiments of strong coupling.

A global defensive alliance in a graph G = (V, E) is a set of vertices S ⊆ V with the properties that every vertex in V - S has at least one neighbor in S, and for each vertex v in S at least half the vertices from the closed neighborhood of v are in S. The alliance is called strong if a strict majority of vertices from the closed neighborhood of v are in S. The global defensive alliance number γa(G) (respectively, global strong defensive alliance number γâ(G)) is the minimum cardinality of a global defensive alliance (respectively, global strong defensive alliance) of G. We show that if T is a tree with order n ≥ 2, l leaves and s support vertices, then γâ (T) ≥ (3n - l - s + 4) /6 and γa (T) ≥ (3n - l - s + 4)/8. Moreover, all extremal trees attaining each bound are characterized.

A global strong defensive alliance in a graph G = (V, E) is a dominating set S of G satisfying the condition that for every vertex ∈ S, the number of neighbors v has in S is at least as large as the number of neighbors it has in V - S. Because of such an alliance, the vertices in S, agreeing to mutually support each other, have the strength of numbers to be able to defend themselves from the vertices in V - S. The global strong alliance number is the minimum cardinality of a global strong defensive alliance in G. We provide a constructive characterization of trees with equal domination and global strong alliance number.

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第18402号 / 情博第517号 / 新制||情||91(附属図書館) / 31260 / 京都大学大学院情報学研究科複雑系科学専攻 / (主査)教授 山本 裕, 教授 西村 直志, 教授 太田 快人 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21461号 / 工博第4536号 / 新制||工||1707(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 松島 信一, 教授 竹脇 出, 教授 池田 芳樹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Last decade witnessed the explosive growth in mobile devices and their traffic demand, and hence the significant increase in the energy cost of the cellular service providers. One major component of energy expenditure comes from the operation of base stations. How to reduce energy cost of base stations while satisfying users’ soaring demands has become an imperative yet challenging problem. In this dissertation, we investigate the minimization of the long-term time-averaged expected energy cost while guaranteeing network strong stability. Specifically, considering flow routing, link scheduling, and energy constraints, we formulate a time-coupling stochastic Mixed-Integer Non-Linear Programming (MINLP) problem, which is prohibitively expensive to solve. We reformulate the problem by employing Lyapunov optimization theory and develop a decomposition based algorithm which ensures network strong stability. We obtain the bounds on the optimal result of the original problem and demonstrate the tightness of the bounds and the efficacy of the proposed scheme.