Abstract

Coherence properties and interference effects allow a quantum particle wavefunction to spread in the fastest possible way inside ordered lattices [1, 2]. In fact, the properties of ballistic diffusion in quantum walks have been widely studied and found applications to energy transport problems [3] and quantum information, generating proposals of search algorithms [4] and universal models for quantum computation [5] with polynomial as well as exponential speed-up [6]. However, in the presence of strong disorder, localization phenomena may quench such a rapid diffusion process [7]. Interestingly, the interplay of interference and noise effects can further enhance quantum transport over complex networks [8], as recently observed for energy transport phenomena in light-harvesting proteins [9–11] and proposed for noise-assisted quantum communication [12].

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