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arXiv · 2004.13055

Bare-Excitation Ground State of a Spinless-Fermion -- Boson Model and $W$-State Engineering in an Array of Superconducting Qubits and Resonators

Vladimir M. Stojanovic
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Abstract

This work unravels an interesting property of a one-dimensional lattice model that describes a single itinerant spinless fermion (excitation) coupled to zero-dimensional (dispersionless) bosons through two different nonlocal-coupling mechanisms. Namely, below a critical value of the effective excitation-boson coupling strength the exact ground state of this model is the zero-quasimomentum Bloch state of a bare (i.e., completely undressed) excitation. It is demonstrated here how this last property of the lattice model under consideration can be exploited for a fast, deterministic preparation of multipartite $W$ states in a readily realizable system of inductively-coupled superconducting qubits and microwave resonators.

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Vladimir M. Stojanovic. 2020-04-27. Bare-Excitation Ground State of a Spinless-Fermion -- Boson Model and $W$-State Engineering in an Array of Superconducting Qubits and Resonators. https://doi.org/10.1103/physrevlett.124.190504

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