Quantum walks driven by quantum coins with two multiple eigenvalues
- URL: http://arxiv.org/abs/2110.00716v1
- Date: Sat, 2 Oct 2021 03:23:51 GMT
- Title: Quantum walks driven by quantum coins with two multiple eigenvalues
- Authors: Norio Konno, Iwao Sato, Etsuo Segawa, Yutaka Shikano
- Abstract summary: We consider a spectral analysis on the quantum walks on graph $G=(V,E)$ with the local coin operators $C_u_uin V$ and the flip flop shift.
We show that this quantum walk can be into a cellular automaton on $ell2(V;mathbbCp)$ whose time evolution is described by a self adjoint operator $T$ and its remainder.
- Score: 0.0
- License: http://creativecommons.org/publicdomain/zero/1.0/
- Abstract: We consider a spectral analysis on the quantum walks on graph $G=(V,E)$ with
the local coin operators $\{C_u\}_{u\in V}$ and the flip flop shift. The
quantum coin operators have commonly two distinct eigenvalues $\kappa,\kappa'$
and $p=\dim(\ker(\kappa-C_u))$ for any $u\in V$ with $1\leq p\leq \delta(G)$,
where $\delta(G)$ is the minimum degrees of $G$. We show that this quantum walk
can be decomposed into a cellular automaton on $\ell^2(V;\mathbb{C}^p)$ whose
time evolution is described by a self adjoint operator $T$ and its remainder.
We obtain how the eigenvalues and its eigenspace of $T$ are lifted up to as
those of the original quantum walk. As an application, we express the
eigenpolynomial of the Grover walk on $\mathbb{Z}^d$ with the moving shift in
the Fourier space.
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