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arXiv · 1312.3157

Non-unitarity and non-reciprocity in scattering from real potentials in presence of confined non-linearity

Zafar Ahmed
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Abstract

Investigations of scattering in presence of non-linearity which have just begun require the confinement of both the potential, $V(x)$, and the non-linearity, $γf(|ψ|)$. There could be two options for the confinement. One is the finite support on $x \in [-L,L]$ and the other one is on $x \in [0,L]$. Here, we consider real Hermitian potentials and report a surprising disparate behaviour of these two types of confinements. We prove that in the first option the symmetric potential enjoys reciprocity of both reflectivity ($R$) and transmitivity ($T$) and their unitarity. More interestingly, the asymmetry in $V(x)$ causes non-unitarity ($ R+T\ne 1$) and the non-reciprocity (reciprocity) of $T (R)$. On the other hand, the second option of confinement gives rise to an essential non-unitarity even when $V(x)$ is symmetric about a point in $[0,L]$. In the absence of symmetry there occurs non-reciprocity of both $R$ and $T$.

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Zafar Ahmed. 2013-12-11. Non-unitarity and non-reciprocity in scattering from real potentials in presence of confined non-linearity. https://arxiv.org/abs/1312.3157

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