Probability backflow for correlated quantum states
Research output: Contribution to journal › Article › peer-review
In its original formulation, quantum backflow (QB) is an interference effect that manifests itself as a negative probability transfer for free-particle states comprised of plane waves with only positive momenta. Quantum reentry (QR) is another interference effect in which a wave packet expanding from a spatial region of its initial confinement partially returns to the region in the absence of any external forces. Here we show that both QB and QR are special cases of a more general classically forbidden probability flow for quantum states with certain position-momentum correlations. We further demonstrate that it is possible to construct correlated quantum states for which the amount of probability transferred in the “wrong” (classically impossible) direction exceeds the least upper bound on the corresponding probability transfer in the QB and QR problems, known as the Bracken-Melloy constant.
|Number of pages||10|
|Journal||Physical Review Research|
|Publication status||Published - 6 Aug 2020|
Final published version, 396 KB, PDF document
Licence: CC BY