Dissipation engineered directional filter for quantum ratchets (A5, C4)

Zlata Fedorova, Christoph Dauer, Anna Sidorenko, Sebastian Eggert, Johann Kroha, and Stefan Linden:

🔓 Phys. Rev. Research 3, 013260 (2021)

We demonstrate transport rectification in a Hermitian Hamiltonian quantum ratchet by a dissipative, dynamic impurity. While the bulk of the ratchet supports transport in both directions, the properly designed loss function of the local impurity acts as a direction-dependent filter for the moving states. We analyze this scheme theoretically by making use of Floquet S-matrix theory. In addition, we provide direct experimental observation of one-way transmittance in periodically modulated plasmonic waveguide arrays containing a local impurity with engineered losses.