Laser acceleration of monoenergetic protons via a double layer emerging from an ultra-thin foil

We present theoretical and numerical studies of the acceleration of monoenergetic protons in a double layer formed by the laser irradiation of an ultra-thin film. The ponderomotive force of the laser light pushes the electrons forward, and the induced space charge electric field pulls the ions and makes the thin foil accelerate as a whole. The ions trapped by the combined electric field and inertial force in the accelerated frame, together with the electrons trapped in the well of the ponderomotive and ion electric field, form a stable double layer. The trapped ions are accelerated to monoenergetic energies up to 100 MeV and beyond, making them suitable for cancer treatment. We present an analytic theory for the laser-accelerated ion energy and for the amount of trapped ions as functions of the laser intensity, foil thickness and the plasma number density. We also discuss the underlying physics of the trapped and untrapped ions in a double layer. The analytical results are compared with those obtained from direct Vlasov simulations of the fully nonlinear electron and ion dynamics that is controlled by the laser light

Scalable Quantum Computation of Highly Excited Eigenstates with Spectral Transforms

We propose a natural application of Quantum Linear Systems Problem (QLSP) solvers such as the HHL algorithm to efficiently prepare highly excited interior eigenstates of physical Hamiltonians in a variational manner. This is enabled by the efficient computation of inverse expectation values, taking advantage of the QLSP solvers' exponentially better scaling in problem size without concealing exponentially costly pre/post-processing steps that usually accompanies it. We detail implementations of this scheme for both fault-tolerant and near-term quantum computers, analyse their efficiency and implementability, and discuss applications and simulation results in many-body physics and quantum chemistry that demonstrate its superior effectiveness and scalability over existing approaches.Comment: 16 pages, 6 figure

Computation of the p6 order chiral Lagrangian coefficients from the underlying theory of QCD

We present results of computing the p6 order low energy constants in the normal part of chiral Lagrangian both for two and three flavor pseudo-scalar mesons. This is a generalization of our previous work on calculating the p4 order coefficients of the chiral Lagrangian in terms of the quark self energy Sigma(p2) approximately from QCD. We show that most of our results are consistent with those we can find in the literature.Comment: 51 pages,2 figure

Social Media Sentiment and Stock Return: A Signalling Theory Explanation for Application of the Natural Langrage Processing Approaches

Social media, especially microblogs, have potentials to develop significant unavoidable factors in investment decision-making, because of its use for capturing human sentiment. In this paper, by applying Signalling theory and Natural Language Processing (NLP) technique, we concern social media sentiment as a signal to stock return which is based on human the sentiment, which may lead to price fluctuation in the market. We take the strength of signal into consideration, introducing the sentiment of traditional media to compare with social media sentiment in different industry. The empirical result of this paper will prove the relationship between social media sentiment and stock return. It will also reflect on analyzing the changes of stock price given different strength of signals in both positive and negative way. The entire study will be viewed as a guideline for investors to filter and smartly use the huge numbers of information when making investment decision