Enhanced quantum teleportation in the background of Schwarzschild spacetime by weak measurements

It is commonly believed that the fidelity of quantum teleportation in the gravitational field would be degraded due to the heat up by the Hawking radiation. In this paper, we point out that the Hawking effect could be eliminated by the combined action of pre- and post-weak measurements, and thus the teleportation fidelity is almost completely protected. It is intriguing to notice that the enhancement of fidelity could not be attributed to the improvement of entanglement, but rather to the probabilistic nature of weak measurements. Our work extends the ability of weak measurements as a quantum technique to battle against gravitational decoherence in relativistic quantum information.Comment: 9 pages, 5 figures, comments are welcom

Enhancing teleportation of quantum Fisher information by partial measurements

The purport of quantum teleportation is to completely transfer information from one party to another distant partner. However, from the perspective of parameter estimation, it is the information carried by a particular parameter, not the information of total quantum state that needs to be teleported. Due to the inevitable noise in environment, we propose two schemes to enhance quantum Fisher information (QFI) teleportation under amplitude damping noise with the technique of partial measurements. We find that post partial measurement can greatly enhance the teleported QFI, while the combination of prior partial measurement and post partial measurement reversal could completely eliminate the effect of decoherence. We show that, somewhat consequentially, enhancing QFI teleportation is more economic than that of improving fidelity teleportation. Our work extends the ability of partial measurements as a quantum technique to battle decoherence in quantum information processing.Comment: Revised version, minor changes, accepted by Phys. Rev.

Protecting entanglement from correlated amplitude damping channel using weak measurement and quantum measurement reversal

Based on the quantum technique of weak measurement, we propose a scheme to protect the entanglement from correlated amplitude damping decoherence. In contrast to the results of memoryless amplitude damping channel, we show that the memory effects play a significant role in the suppression of entanglement sudden death and protection of entanglement under severe decoherence. Moreover, we find that the initial entanglement could be drastically amplified by the combination of weak measurement and quantum measurement reversal even under the correlated amplitude damping channel. The underlying mechanism can be attributed to the probabilistic nature of weak measurements.Comment: 11 pages, 5 figures, accepted by Quantum Information Processin

Novel research methods for estimating the impact of energy use on ecological environment: evidence from B.R.I.C.S. economies

The current study looked at the influence of fossil-fuel energy (E.U.) consumption, renewable power generation and greenhouse gas emissions in Brazil, Russia, India, China, and South Africa (B.R.I.C.S.) between 1990 and 2020. The latest study also takes into account the influence of gross domestic product (G.D.P.) and technological innovation on carbon emissions. Using cross-sectional dependence and slope heterogeneity, the order of the unit root is also determined. The findings acquired by the application of moment quantile regression. The research finds that G.D.P. and the usage of E.U. increase carbon emissions at the 25th, 50th, 75th and 90th quantiles. On the other hand, renewable energy generation and technical innovation reduce carbon emissions at the 25th, 50th, 75th and 90th quantiles. Furthermore, while implementing B.R.I.C.S. economies’ energy, environment, and growth policies based on empirical data, policymakers should analyse the asymmetry behaviour of G.D.P., E.U. consumption, renewable power output and technological innovation

Performance Analysis of Metamaterials With Two-dimensional Isotropy

A two-dimensional isotropic metamaterials formed by crossed split-ring resonators (CSRRs) are studied in this paper. The effective characteristic parameters of this media are determined by quasi-static Lorentz theory. The induced current distributions of a single CSRR at the resonant frequency are presented. Moreover, the dependence of the resonant frequency on the dimensions of single CSRR and the spaces of the array are also discussed.Singapore-MIT Alliance (SMA

Advancing inverse scattering with surrogate modeling and Bayesian inference for functional inputs

Inverse scattering aims to infer information about a hidden object by using the received scattered waves and training data collected from forward mathematical models. Recent advances in computing have led to increasing attention towards functional inverse inference, which can reveal more detailed properties of a hidden object. However, rigorous studies on functional inverse, including the reconstruction of the functional input and quantification of uncertainty, remain scarce. Motivated by an inverse scattering problem where the objective is to infer the functional input representing the refractive index of a bounded scatterer, a new Bayesian framework is proposed. It contains a surrogate model that takes into account the functional inputs directly through kernel functions, and a Bayesian procedure that infers functional inputs through the posterior distribution. Furthermore, the proposed Bayesian framework is extended to reconstruct functional inverse by integrating multi-fidelity simulations, including a high-fidelity simulator solved by finite element methods and a low-fidelity simulator called the Born approximation. When compared with existing alternatives developed by finite basis expansion, the proposed method provides more accurate functional recoveries with smaller prediction variations