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arXiv · 1404.2070

Quantum Non-Abelian Hydrodynamics: Anyonic or Spin-Orbital Entangled liquids, Non-Unitarity of Scattering matrix and Charge Fractionalization

Abstract

In this article we develop an exact(non-adiabatic,non-perturbative) density matrix scattering theory for a two component quantum liquid which interacts or scatters off from a generic spin-dependent quantum potential. We find that the number or charge density in scattered fluid,$\text{Tr}({\varrho}_{sc})$ depends on {non-trivial quantum interference coefficients}, ${\cal{Q}}^{αβ}_{0ijk}$ which arises due to quantum interference between spin-independent and spin-dependent scattering amplitudes and among spin-dependent scattering amplitudes. The effect of quantum interference coefficients can be include by defining a {\bf vector order parameter} $\bm{Q}$. We find that in presence of spin-dependent interaction the {\bf vector order parameter} $\bm{Q}$ is necessarily non-zero and is related to the commutator and anti-commutator of scattering matrix $\cal{S}$ with its dagger $\cal{S}^{\dagger}$. It is further shown that $\bm{Q}\neq 0$, implies four physically equivalent conditions,i.e, {\bf spin-orbital entanglement is non-zero}, {\bf Non-Abelian scattering phase,i.e, matrices}, scattering matrix is {\bf Non-Unitary} and the broken time reversal symmetry for scattered density matrix. This also implies that quasi particle excitation are anyonic in nature, hence, charge fractionalization is a natural consequence. This aspect has also been discussed from the perspective of number or charge density conservation, which implies i.e, $\text{Tr}({\varrho}_{sc})=\text{Tr}({\varrho}_{in})$. On the other hand $\bm{Q}=0$ turns out to be a mathematically forced unphysical solution in presence of spin-dependent potential or scattering which is equivalent to {\bf Abelian} hydrodynamics ,{\bf Unitary} scattering matrix, absence of spin-space entanglement, and preserved time reversal symmetry.

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Tribhuvan Prasad Pareek. 2014-04-15. Quantum Non-Abelian Hydrodynamics: Anyonic or Spin-Orbital Entangled liquids, Non-Unitarity of Scattering matrix and Charge Fractionalization. https://arxiv.org/abs/1404.2070

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