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arXiv · 1804.06488

Exactly solvable quantum impurity model with inverse-square interactions

Hong-Hao Tu·Ying-Hai Wu
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Abstract

We construct an exactly solvable quantum impurity model which consists of spin-1/2 conduction fermions and the spin-1/2 magnetic moment. The ground state is a Gutzwiller projected Fermi sea with non-orthonormal modes and its wave function in the site-occupation basis is a Jastrow-type homogeneous polynomial. The parent Hamiltonian has all-to-all inverse-square hopping terms between the conduction fermions and inverse-square spin-exchange terms between the conduction fermions and the magnetic moments. The low-lying energy levels, spin-spin correlation function, and von Neumann entanglement entropy of our model demonstrate that it exhibits the essential aspects of spin-1/2 Kondo physics. The machinery developed in this work can generate many other exactly solvable quantum impurity models.

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Hong-Hao Tu, Ying-Hai Wu. 2019-08-11. Exactly solvable quantum impurity model with inverse-square interactions. https://doi.org/10.1103/physrevlett.123.066406

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