Bound states in the continuum in electronic transport through parallel‐coupled quantum‐dot structures

Abstract

The occurrence of bound states in continuum (BICs) are theoretically studied, by investigating the electronic transport through coupled quantum‐dot structures (a quantum‐dot chain and a quantum‐dot ring) embodied in an Aharonov–Bohm interferometer. It is found that for the structure of a quantum‐dot chain, the BICs will come into being only under the condition of the same‐numbered quantum dots coupled to the quantum dots in the arms of the interferometer. But with respect to the quantum‐dot ring, the occurrence of BICs is remarkable, independent of the number of quantum dots in the ring. Furthermore, by the presence of an appropriate magnetic flux through the interferometer, the linear conductance spectrum of the (2n + 1)‐quantum‐dot ring (n ∈ integer) is the same as that of the 2n ‐quantum‐dot chain, on account of the occurrence of BICs in electron transport through these two kinds of systems. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Line-defect–induced Fano interference in an armchair graphene nanoribbon

“…The conclusion is the same, namely, when the localized states appear in the main conduction channel, the Fano antiresonance will come into being. In fact, for analyzing the localized states, one suitable method is to transform the Hamiltonian into its molecular-orbit representation, which helps to clarify the localized-state positions and the couplings between the localized states and the leads [44,47]. In some other GNRs, if the antiresonance originates from the alternate mechanisms, such as the edge state [48] or the twofold degenerate resonant levels [10], the antiresonance position can be solved exactly.…”

Quasi-BICs Enabled Proximity Sensing Based on Metal Complementary H-Shaped Arrays at Terahertz Frequencies

“…When both the Q-factor and the resonant width become limited, BICs turn into quasi-BICs or the so-called super cavity modes [11], which appear as a Fano line with an ultra-high Q value [12][13][14][15][16][17][18]. The quasi-BICs offers great potential for application in the fields of ultra-sensitive sensors [18] and ultra-narrowband filters [16,[19][20][21][22][23].…”