arXiv subjects

Jing Chen

Publications and source records attributed to Jing Chen.

313 records · Page 18Linked to original sources

arXiv2008

The Goldbeter-Koshland switch in the first-order region and its response to dynamic disorder

In their classical work (Proc. Natl. Acad. Sci. USA, 1981, 78:6840-6844), Goldbeter and Koshland mathematically analyzed a reversible covalent modification system which is highly sensitive to the concentration of effectors. Its signal-response curve appears sigmoidal, constituting a biochemical switch. However, the switch behavior only emerges in the "zero-order region", i.e. when the signal molecule concentration is much lower than that of the substrate it modifies. In this work we showed that the switching behavior can also occur under comparable concentrations of signals and substrates, provided that the signal molecules catalyze the modification reaction in cooperation. We also studied the effect of dynamic disorders on the proposed biochemical switch, in which the enzymatic reaction rates, instead of constant, appear as stochastic functions of time. We showed that the system is robust to dynamic disorder at bulk concentration. But if the dynamic disorder is quasi-static, large fluctuations of the switch response behavior may be observed at low concentrations. Such fluctuation is relevant to many biological functions. It can be reduced by either increasing the conformation interconversion rate of the protein, or correlating the enzymatic reaction rates in the network.

q-bio.MN↗

arXiv2007

Classical Trajectory Perspective on Double Ionization Dynamics of Diatomic Molecules Irradiated by Ultrashort Intense Laser Pulses

In the present paper, we develop a semiclassical quasi-static model accounting for molecular double ionization in an intense laser pulse. With this model, we achieve insight into the dynamics of two highly-correlated valence electrons under the combined influence of a two-center Coulomb potential and an intense laser field, and reveal the significant influence of molecular alignment on the ratio of double over single ion yield. Analysis on the classical trajectories unveils sub-cycle dynamics of the molecular double ionization. Many interesting features, such as the accumulation of emitted electrons in the first and third quadrants of parallel momentum plane, the regular pattern of correlated momentum with respect to the time delay between closest collision and ionization moment, are revealed and successfully explained by back analyzing the classical trajectories. Quantitative agreement with experimental data over a wide range of laser intensities from tunneling to over-the-barrier regime is presented.

physics.atm-clus↗

arXiv2006

Charge-Resonance Effect on Harmonic Generation by Symmetric Diatomic Molecular Ions in Intense Laser Fields

In present paper we develop an analytic theory for the harmonic generation of symmetric diatomic molecular ions beyond two-level model, emphasizing the influence of charge-resonance (CR) states those are strongly coupled to electromagnetic fields for large internuclear distance. With taking into account the continuum states that is ignored in the two-level model and become important for intense laser case, our model is capable to produce spectrum for the whole range of harmonic orders consisting of a molecular plateau due to the CR transition and an atomic-like plateau for a long-wavelength excitation, and in good agreement with numerical results from directly solution of the Schrödinger equation. Our theory also identifies the crucial role of the CR states in the fine structure of harmonic spectrum and shows that the harmonic generation in molecular system can be effectively controlled by adjusting the internuclear distance.

physics.atom-ph↗

arXiv2005

The Physical Foundation of Human Mind and a New Theory of Investment

This paper consists of two parts. In the first part, we develop a new information theory, in which it is not a coincidence that information and physical entropy share the same mathematical formula. It is an adaptation of mind to help search for resources. We then show that psychological patterns either reflect the constraints of physical laws or are evolutionary adaptations to efficiently process information and to increase the chance of survival in the environment of our evolutionary past. In the second part, we demonstrate that the new information theory provides the foundation to understand market behavior. One fundamental result from the information theory is that information is costly. In general, information with higher value is more costly. Another fundamental result from the information theory is that the amount of information one can receive is the amount of information generated minus equivocation. The level of equivocation, which is the measure of information asymmetry, is determined by the correlation between the source of information and the receiver of information. In general, how much information one can receive depends on the background knowledge of the receiver. The difference in cost different investors are willing to pay for information and the difference in background knowledge about a particular information causes the heterogeneity in information processing by the investment public, which is the main reason of the price and volume patterns observed in the market. Many assumptions in some of the recent models on behavioral finance can be derived naturally from this theory.

cs.IT↗

arXiv2005

Local field modulated entanglment among three distant atoms

We extend the scheme for that proposed by S. Mancini and S. Bose (Phys. Rev. A \QTR{bf}{70}, 022307(2004)) to the case of triple-atom. Under mean field approximation, we obtain an effective Hamiltonian of triple-body Ising-model interaction. Furthermore, we stress on discussing the influence of the existence of a third-atom on the two-atom entanglement and testing the modulation effects of locally applied optical fields and fiber on the entanglement properties of our system.

quant-ph↗

arXiv2005

An Effective Two-component Entanglement in Double-well Condensation

We propose a spin-half approximation method for two-component condensation in double wells to discuss the quantum entanglement of two components. This approximation is presented to be valid under stationary tunneling effect for odd particle number of each component. The evolution of the entanglement is found to be affected by the particle number both quantitatively and qualitatively. In detail, the maximal entanglement are shown to be hyperbolic like with respect to tunneling rate and time. To successively obtain large and long time sustained entanglement, the particle number should not be large.

quant-ph↗

arXiv2001

Classical collisional trajectories as the source of strong-field double ionization of helium in the knee regime

In this paper, a quasistatic model is extended to describe the double ionization of Helium in intense linearly polarized field, yielding achieve an insight to the two-electron correlation effect in the ionization dynamics. Our numerical calculations reproduce the excessive double ionization and the photoelectron spectra observed experimentally both quantitatively and qualitatively. Moreover, it is shown that the classical collisional trajectories are the main source of the double ionization in the knee regime and responsible for the unusual angular distribution of the photoelectrons.

physics.atom-ph↗