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arXiv · 1401.3108

Complete particle-pair annihilation as a dynamical signature of the spectral singularity

G. R. Li·X. Z. Zhang·Z. Song
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Abstract

Motivated by the physical relevance of a spectral singularity of interacting many-particle system, we explore the dynamics of two bosons as well as fermions in one-dimensional system with imaginary delta interaction strength. Based on the exact solution, it shows that the two-particle collision leads to amplitude-reduction of the wave function. For fermion pair, the amplitude-reduction depends on the spin configuration of two particles. In both cases, the residual amplitude can vanish when the relative group velocity of two single-particle Gaussian wave packets with equal width reaches the magnitude of the interaction strength, exhibiting complete particle-pair annihilation at the spectral singularity.

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G. R. Li, X. Z. Zhang, Z. Song. 2014-01-14. Complete particle-pair annihilation as a dynamical signature of the spectral singularity. https://doi.org/10.1016/j.aop.2014.06.022

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