arXiv subjects

Heekyung Han

Publications and source records attributed to Heekyung Han.

4 recordsLinked to original sources

arXiv2010

Distinguishability and Chiral Stability: Effects of Decoherence and Intermolecular Interactions

We examine the effect of decoherence and intermolecular interactions (chiral discrimination energies) on the chiral stability and the distinguishability of initially pure versus mixed states in an open chiral system. Under a two-level approximation for a system, intermolecular interactions are introduced by a mean-field theory, and interaction between a system and an environment is modeled by a continuous measurement of a population difference between the two chiral states. The resultant equations are explored for various parameters, with emphasis on the combined effects of the initial condition of the system, the chiral discrimination energy and the decoherence. We focus on factors affecting the distinguishability as measured by population difference between the initially pure and mixed states and on the chiral stability as measured by the purity decay.

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arXiv2010

Effects of initial coherence on distinguishability of pure/mixed states and chiral stability in an open chiral system

We examine how initial coherences in open chiral systems affect distinguishability of pure versus mixed states and purity decay. Interaction between a system and an environment is modeled by a continuous position measurement and a two-level approximation is taken for the system. The resultant analytical solution is explored for various parameters, with emphasis on the interplay of initial coherences of the system and dephasing rate in determining the purity decay and differences in the time evolution of pure vs. mixed initial states. %the distinguishability and the decoherence process. Implications of the results on several fundamental problems are noted.

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arXiv2005

Analytic solution to N vs. M photon phase control in an open two-level system

Decoherence effects on the traditional N vs. M photon coherent control of a two-level system are investigated, with 1 vs. 3 used as a specific example. The problem reduces to that of a two-level system interacting with a single mode field, but with an effective Rabi frequency that depends upon the fundamental and third harmonic fields. The resultant analytic control solution is explored for a variety of parameters, with emphasis on the dependence of control on the relative phase of the lasers. The generalization to off-resonant cases is noted.

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arXiv2005

Decoherence Effects in Reactive Scattering

Decoherence effects on quantum and classical dynamics in reactive scattering are examined using a Caldeira-Leggett type model. Through a study of dynamics of the collinear H+H2 reaction and the transmission over simple one-dimensional barrier potentials, we show that decoherence leads to improved agreement between quantum and classical reaction and transmission probabilities, primarily by increasing the energy dispersion in a well defined way. Increased potential nonlinearity is seen to require larger decoherence in order to attain comparable quantum-classical agreement.

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