Transport through a quantum wire with a side quantum-dot array

Abstract

A noninteracting quantum-dot array side coupled to a quantum wire is studied. Transport through the quantum wire is investigated by using a noninteracting Anderson tunneling Hamiltonian. The conductance at zero temperature develops an oscillating band with resonances and antiresonances due to constructive and destructive interference in the ballistic channel, respectively. Moreover, we have found an odd-even parity in the system, whose conductance vanishes for an odd number of quantum dots while it becomes 2e 2 /h for an even number. We established an explicit relation between this odd-even parity and the positions of the resonances and antiresonances of the conductivity with the spectrum of the isolated quantum-dot array.

Non-Hermitian tight-binding network engineering

“…A paradigmatic example of the FanoAnderson model, which is ofter encountered in the theory of coherent transport in mesoscopic condensed-matter systems and in integrated photonic systems, is provided by the coupling of a localized state to an infinite or semiinfinite tight-binding lattice, i.e. to a continuous band of Bloch modes [44,45]. Hermitian coupling (hopping amplitude g real) is the gold standard in such models, however complexification of the coupling constant (g imaginary) is of some interest in certain quantum models, such as the Lee model in the so-called ghost regime [30] or in the theory of the inverted quantum oscillators system is in the unbroken PT phase, with one bound state in region I (the "physical" particle state) and two bound states in region II (the "physical" particle state plus the "ghost").…”

NAND gate response in a mesoscopic ring: an exact result

“…Later, many excellent experiments [2,3,4] have been done in several bridge systems to understand the basic mechanisms underlying the electron transport. Though in literature both theoretical [5,6,7,8,9,10,11,12,13] as well as experimental [2,3,4] works on electron transport are available, yet lot of controversies are still present between the theory and experiment, and the complete knowledge of the conduction mechanism in this scale is not very well established even today. The interface geometry between the ring and the electrodes significantly controls the electronic transport in the ring.…”

Electron transport through mesoscopic rings: Evidence of nano-scale rectifiers

“…Following this pioneering work, several experiments have been done through different bridge systems to reveal the actual mechanism of electron transport. Though, to date a lot of theoretical [5,6,7,8,9,10,11,12,13,14,15,16] as well as experimental works [17,18,19,20] on two-terminal electron transport have been done addressing several important issues, yet the complete knowledge of conduction mechanism in nano-scale systems is still unclear to us. Transport properties are characterized by several significant factors like quantization of energy levels, quantum interference of electronic waves associated with the geometry of bridging system adopts within the junction, etc.…”