The limitations imposed by low current can in theory be mitigated by opening the bias window symmetrically around the resonance of the highest occupied molecular orbital (HOMO). This way the quantum interference feature is avoided and the current is higher than orthoand para-cases while retaining the strong unidirectional ring current (Figure , right column). Due to the high current, the magnetic field locally reaches the mT range inside the benzene ring. While this has yet to be achieved experimentally, it may be possible to open the bias window close to the resonance with a gate electrode. Figure : Current density (top row), and magnetic field (middle and bottom row) of cyclic molecules with bond-length alternation. The magnetic field is plotted as a vector field (middle row) and as the point where the field is strongest (bottom row).