Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Coherent preparation by laser light of quantum states of atoms and molecules can lead to quantum interference in the amplitudes of optical transitions. In this way the optical properties of a medium can be dramatically modified, leading to electromagnetically induced transparency and related effects, which have placed gas-phase systems at the center of recent advances in the development of media with radically new optical properties. This article reviews these advances and the new possibilities they offer for nonlinear optics and quantum information science. As a basis for the theory of electromagnetically induced transparency the authors consider the atomic dynamics and the optical response of the medium to a continuous-wave laser. They then discuss pulse propagation and the adiabatic evolution of field-coupled states and show how coherently prepared media can be used to improve frequency conversion in nonlinear optical mixing experiments. The extension of these concepts to very weak optical fields in the few-photon limit is then examined. The review concludes with a discussion of future prospects and potential new applications.

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Electromagnetically induced transparency : Optics in coherent media

as quantum engineering. In the past two decades it has become increasingly clear that many (perhaps all) of the symptoms of classicality can be induced in quantum systems by their environments. Thus decoherence is caused by the interaction in which the environment in effect monitors certain observables of the system, destroying coherence between the pointer states corresponding to their eigenvalues. This leads to environment-induced superselection or einselection, a quantum process associated with selective loss of information. Einselected pointer states are stable. They can retain correlations with the rest of the universe in spite of the environment. Einselection enforces classicality by imposing an effective ban on the vast majority of the Hilbert space, eliminating especially the flagrantly nonlocal ''Schrodinger-cat states.'' The classical structure of phase space emerges from the quantum Hilbert space in the appropriate macroscopic limit. Combination of einselection with dynamics leads to the idealizations of a point and of a classical trajectory. In measurements, einselection replaces quantum entanglement between the apparatus and the measured system with the classical correlation. Only the preferred pointer observable of the apparatus can store information that has predictive power. When the measured quantum system is microscopic and isolated, this restriction on the predictive utility of its correlations with the macroscopic apparatus results in the effective ''collapse of the wave packet.'' The existential interpretation implied by einselection regards observers as open quantum systems, distinguished only by their ability to acquire, store, and process information. Spreading of the correlations with the effectively classical pointer states throughout the environment allows one to understand ''classical reality'' as a property based on the relatively objective existence of the einselected states. Effectively classical pointer states can be ''found out'' without being re-prepared, e.g, by intercepting the information already present in the environment. The redundancy of the records of pointer states in the environment (which can be thought of as their ''fitness'' in the Darwinian sense) is a measure of their classicality. A new symmetry appears in this setting. Environment-assisted invariance or envariance sheds new light on the nature of ignorance of the state of the system due to quantum correlations with the environment and leads to Born's rules and to reduced density matrices, ultimately justifying basic principles of the program of decoherence and einselection.

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Decoherence, einselection, and the quantum origins of the classical

Microcavity physics and design will be reviewed. Following an overview of applications in quantum optics, communications and biosensing, recent advances in ultra-high-Q research will be presented.

Optical microcavities

The science of quantum information has arisen over the last two decades centered on the manipulation of individual quanta of information, known as quantum bits or qubits. Quantum computers, quantum cryptography, and quantum teleportation are among the most celebrated ideas that have emerged from this new field. It was realized later on that using continuous-variable quantum information carriers, instead of qubits, constitutes an extremely powerful alternative approach to quantum information processing. This review focuses on continuous-variable quantum information processes that rely on any combination of Gaussian states, Gaussian operations, and Gaussian measurements. Interestingly, such a restriction to the Gaussian realm comes with various benefits, since on the theoretical side, simple analytical tools are available and, on the experimental side, optical components effecting Gaussian processes are readily available in the laboratory. Yet, Gaussian quantum information processing opens the way to a wide variety of tasks and applications, including quantum communication, quantum cryptography, quantum computation, quantum teleportation, and quantum state and channel discrimination. This review reports on the state of the art in this field, ranging from the basic theoretical tools and landmark experimental realizations to the most recent successful developments.

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Gaussian quantum information

Recently electromagnetically induced transparency (EIT) was shown to slow down dramatically [1], or even to stop completely, laser pulses in atomic gases [2, 3]. Such behavior can be understood in terms of a branch of slow polaritons appearing between two close atomic resonances, as shown in Fig. 1 (adapted from of ref. [4]). Here we present a general theory of polaritons in atomic BEC, followed by the analysis of the EIT polaritons. The possibility of reverting a stopped polariton is demonstrated.

Slow Polaritons in Atomic Bose-Einstein Condensates

We have now developed the bulk of the formalism we need and can turn our attention to rather more ambitious applications than the damped harmonic oscillator and the damped two-level atom. We restrict our attention in this book to the single-mode laser. In Volume 2 we consider the degenerate parametric oscillator and cavity QED. As can be judged from a quick look at Haken’s book on laser theory [7.1], the first of these examples can easily fill a book on its own. We will therefore have to be rather selective in what we cover in two chapters. Our main objective is to illustrate the things we have learned in a practical application: the derivation of a master equation and associated phase-space equation of motion, the reduction of the phase-space equation to a manageable form using van Kampen’s system size expansion, and the extraction of useful results from the resulting stochastic model. The topics that we address are covered in sections V and VI of Haken’s book. The treatment will be similar to the one found there; although, we do not follow Haken’s notation, and we will fill in the details in some of his calculations. The laser Fokker—Planck equation is derived using somewhat different methods by Louisell [7.2]. Laser theory can also be built around density matrix equations, following the approach of Scully and Lamb [7.3]. For a comparison with the phase-space method, the Scully-Lamb theory can be studied in the text by Sargent, Scully and Lamb [7.4].

The Single-Mode Homogeneously Broadened Laser I: Preliminaries

http://link.springer.com/content/pdf/10.1007/978-3-642-74951-3_17.pdf

Modulation Spectroscopy and Cavity QED

We revisit the “trapping states” of the micromaser from a quantum trajectory point of view, treating many simultaneously interacting atoms and a random atomic beam. Previous studies of trapping states are severely restricted by simplifying assumptions. We show that sub-Poissonian maser fields are generated still after the principal restrictions are lifted.

“Trapping states” — Revisited

It is shown how to implement quantum feedback and probabilistic error correction in an open quantum system consisting of a single atom, with ground- and excited-state Zeeman structure, in a driven two-mode optical cavity. The ground state superposition is manipulated and controlled through conditional measurements and external fields, which shield the coherence and correct quantum errors. Modeling of an experimentally realistic situation demonstrates the robustness of the proposal for realization in the laboratory.

Howard J. Carmichael

Papers

Slow Polaritons in Atomic Bose-Einstein Condensates

The Single-Mode Homogeneously Broadened Laser I: Preliminaries

Modulation Spectroscopy and Cavity QED

“Trapping states” — Revisited

From quantum feedback to probabilistic error correction: Manipulation of quantum beats in cavity QED