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arXiv · 1604.06604

Rogue wavefunctions due to noisy quantum tunneling potentials

Abstract

In this paper we study the effects of white-noised potentials on nonlinear quantum tunneling. We use a split-step scheme to numerically solve the nonlinear Schrodinger equation (NLSE) with a tunneling potential. We consider three different types of potentials, namely; the single rectangular barrier, double rectangular barrier and triangular barrier. For all these three cases we show that white-noise given to potentials do not trigger modulation instability for tunneling of the sech type soliton solutions of the NLSE. However white-noised potentials trigger modulation instability for tunneling of the sinusoidal wavefunctions, thus such a wavefield turns into a chaotic one with many apparent peaks. We argue that peaks of such a field may be in the form of rational rogue wave solutions of the NLSE. Our results can be used to examine the effects of noise on quantum tunneling. Since a rogue wavefunction means a higher probability of the tunneling particle to be at a given (x,t) coordinate, our results may also be used for developing the quantum science and technology with many possible applications including but are not limited to increasing the resolution and efficiency of scanning tunneling microscopes, enhancing proton tunneling for DNA mutation and enhancing superconducting properties of junctions.

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Cihan Ahmet Bayındır. 2016-04-22. Rogue wavefunctions due to noisy quantum tunneling potentials. https://arxiv.org/abs/1604.06604

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