Dynamically disordered quantum walk as a maximal entanglement generator
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Updated: May 5, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Rafael Vieira1, Edgard P M Amorim, Gustavo Rigolin
1Departamento de Física, Universidade do Estado de Santa Catarina, 89219-710 Joinville, Santa Catarina, Brazil.
Abstract:
We show that the entanglement between the internal (spin) and external (position) degrees of freedom of a qubit in a random (dynamically disordered) one-dimensional discrete time quantum random walk (QRW) achieves its maximal possible value asymptotically in the number of steps, outperforming the entanglement attained by using ordered QRW. The disorder is modeled by introducing an extra random aspect to QRW, a classical coin that randomly dictates which quantum coin drives the system's time evolution. We also show that maximal entanglement is achieved independently of the initial state of the walker, study the number of steps the system must move to be within a small fixed neighborhood of its asymptotic limit, and propose two experiments where these ideas can be tested.
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