| We investigate transport properties of the nonadiabatically pumped double-quantum-well(DQW)structure and three-band pseudospin-1 Dirac-Weyl systems.Due to be different from a single quantum well,band mixing in the DQW generates bonding and antibonding states.Meanwhile their wave functions have different spatial symmetry.By applying a time-dependent electric potential to the two well regions simultaneously,Floquet sidebands are formed,which constitutes additional quantum tunneling paths.When one of the Floquet sidebands coincides with the bonding or antibonding quasibound states within the DQW structure,sharp Fano resonances are found in the transmission coefficients as well as in the differential shot noise spectra.While such Fano resonances originate from quantum interference,their shapes are strikingly different for transport via the bonding state and via the antibonding state.The Fano resonance via the even-parity bonding state shows a perfect transmission followed by a total reflection and the Fano resonance via the odd-parity antibonding state has a reversed symmetry and shows a total reflection before a perfect transmission.At the same time,we extend related studies to the three-band pseudospin-1 Dirac-Weyl systems.We investigate quasi-bound states and nonadiabatically pumped shot noise in pseudospin-1 quantum wells.In comparison with graphene,we found that the three-band pseudospin-1 Dirac–Weyl quantum well confines more bound states and parities of these bound-state wave functions are different.These differences have an effect on the quantum interference processes through the bound state,which are reflected in the Fano resonance spectrum in the nonadiabatic transmission and shot noise.We attribute the overall behavioral difference between graphene and the pseudospin-1 system to the topological difference in their band structure.Research suggests the nonadiabatically induced Fano resonance as a promising way to diagnose deeply into wavefunction profiles of quantum systems. |
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