Quantum network architecture of tight-binding models with substitution sequences

Abstract We study a two-spin quantum Turing architecture, in which discrete local rotations {αm} of the Turing head spin alternate with quantum controlled NOT operations. Substitution sequences are known to underlie aperiodic structures. We show that parameter inputs {αm} described by such sequences can lead here to a quantum dynamics, intermediate between the regular and the chaotic variant. Exponential parameter sensitivity characterizing chaotic quantum Turing machines turns out to be an adequate criterion for induced quantum chaos in a quantum network.