Probing quantum discord and coherence dynamics in the discrete-time quantum walk under generalized amplitude damping noise channel

Abstract

We investigate the behaviour of one-dimensional dissipative Hadamard discrete-time quantum walk (DTQW) in the generalized amplitude damping channel. By manipulating the noise intensity, we uncover intriguing dynamics in the coherence of the coin state such as rebounding and freezing phenomena. The entanglement between the quantum walker’ states diminishes at lower dissipation rates despite the pronounced coherence. The non-classical characters of the dissipative DTQW becomes evident through the manifestation of quantum discord. Our study shows that even under maximum dissipation stemming from both zero and finite-temperature environment, the quantum walker retains rudimentary non-classical behaviours. It is shown that fine-tuning the parameter governing the coin rotation angle optimizes the quantum discord of the walker. These results are useful for optimizing quantum walks in the presence of noisy channels.