Probing the antisymmetric Fano interference assisted by a Majorana fermion

Abstract

The Aharonov-Bohm-Fano interferometer as a spin-manipulating device J. Appl. Phys. 109, 074315 (2011); 10.1063/1.3559270 Coulomb-modified equilibrium and nonequilibrium properties in a double quantum dot Aharonov-Bohm-Fano interference device J. Appl. Phys. 107, 073702 (2010); 10.1063/1.3311641 Impurity-modified Fano effect in a double quantum dot Aharonov-Bohm interferometerAs the Fano effect is an interference phenomenon where tunneling paths compete for the electronic transport, it becomes a probe to catch fingerprints of Majorana fermions lying on condensed matter systems. In this work, we benefit of this mechanism by proposing as a route for that an Aharonov-Bohm-like interferometer composed by two quantum dots, being one of them coupled to a Majorana bound state, which is attached to one of the edges of a semi-infinite Kitaev wire within the topological phase. By changing the Fermi energy of the leads and the symmetric detuning of the levels for the dots, we show that opposing Fano regimes result in a transmittance characterized by distinct conducting and insulating regions, which are fingerprints of an isolated Majorana quasiparticle. Furthermore, we show that the maximum fluctuation of the transmittance as a function of the detuning is half for a semi-infinite wire, while it corresponds to the unity for a finite system. The setup proposed here constitutes an alternative experimental tool to detect Majorana excitations. V C 2014 AIP Publishing LLC. [http://dx.

Unveiling Majorana quasiparticles by a quantum phase transition: Proposal of a current switch

“…For t = ∆, we recover the Green's functions derived in Refs. [28] and [29]. In such works, we point out that the profiles of T (ε, t = ∆) as a function of the single particle energy ε for a given symmetric detuning ∆ε of the QDs appear analyzed in great detail, since this case corresponds to the unique presence of a Kitaev chain.…”

“…We then suggest the reader to see Refs. [28] and [29] where T (ε, t = ∆) versus ε for finite values of ∆ε can be found. In the limit of t = ∆, we have checked that the Majorana ZB anomaly (peak or dip) is not verified.…”

All-optical scheme for detecting the possible Majorana signature based on QD and nanomechanical resonator systems

“…Compared with the electrical detection scheme where the QD is coupled to MF via tunneling [66][67][68][69][70][71][72][73][74][75][76], in our optical scheme, the QD-MF coupling is mainly due to dipoledipole interaction. As in current experiments the distance between QD and MF can be adjusted to about several tens of nanometers, in this case, the tunneling between the QD and MF can be neglected.…”

“…As each MF is its own antiparticle, an operator γ with γ † = γ and γ 2 = 1 to describe MFs is introduced. Suppose that the QD couples to γ 1 , then the Hamiltonian is written by as [66][67][68][69][70][71][72][73][74][75][76]:…”

“…To detect MFs, QDs [66][67][68][69][70][71][72][73][74][75][76] and NRs [77,78] as intermediates are used to probe Majorana signature via tunneling experiments. Most of the schemes to detect MFs have focused on the electronic transport properties, which can be significantly altered by MFs and will exhibit signatures such as the zero-bias peak in conductance [15][16][17][18][19].…”