Distinguishing Majorana bound states from Andreev bound states through differential conductance and current noise spectrum

Abstract

We investigate the quantum transport through a quantum dot coupled with a superconducting (SC) nanowire. By elaborating the differential conductance and current noise spectrum, we focus on the distinct characteristics of the topological Majorana bound states (MBSs) and trivial Andereev bound states (ABSs) hosted in SC wire. For MBSs with a topological quality factor $q=1$, we observe the degenerate features manifested as the zero-bias peak (ZBP) in differential conductance and the Rabi dips degeneracy (RDD) in noise spectrum. In contrast, for ABSs with $q<1$, the splitting of these degenerate features depends on the linewidth, arising from realistic measurement conditions. Furthermore, we identify the critical quality factors $q_{\mathrm{c}}$ and $q_{\mathrm{s}}$ associated with the emergences of ZBP and RDD, respectively. The value of $q_{\mathrm{c}}$ is temperature-dependent, and we establish a suitable temperature window to ensure the visibility of single ZBP in the experiments. Whereas, $q_{\mathrm{c}}$ depends on the coupling strength rather than the temperature. Typical values for these quality factors are approximately $q_{\mathrm{c}}\approx 0.93$ and $q_{\mathrm{s}}\approx 0.99$. Our results suggest that the degenerate Rabi spectrum signal could serve as a hallmark for the presence of MBSs, which goes beyond the scope of differential conductance.

10 pages, 4 figures

References in corpus (25)

• Non-Abelian Anyons and Topological Quantum Computation
• Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices
• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Evidence of Majorana fermions in an Al - InAs nanowire topological superconductor
• Observation of Majorana Fermions in a Nb-InSb Nanowire-Nb Hybrid Quantum Device
• Anomalous modulation of a zero bias peak in a hybrid nanowire-superconductor device
• Observing Majorana Bound States in p-wave Superconductors Using Noise Measurements in Tunneling Experiments
• SNS junctions in nanowires with spin-orbit coupling: role of confinement and helicity on the sub-gap spectrum
• Probing Majorana Physics in Quantum Dot Shot Noise Experiments
• Spontaneous Relaxation of a Charge Qubit under Electrical Measurement
• Asymmetric Quantum Shot Noise in Quantum Dots
• Calculation of the current noise spectrum in mesoscopic transport: an efficient quantum master equation approach
• Readout of Majorana Qubits
• Non-Markovian effects in the Quantum noise of interacting nanostructures
• Parity-to-charge conversion in Majorana qubit readout
• The noise spectra of a biased quantum dot
• Current noise cross correlation mediated by Majorana bound states
• Steps and dips in the ac conductance and noise of mesoscopic structures
• Majorana finite frequency nonequilibrium quantum noise
• Probing Robust Majorana Signatures by Crossed Andreev Reflection with a Quantum Dot
• Enhanced current noise correlations in a Coulomb-Majorana device
• Finite-frequency current (shot) noise in coherent resonant tunneling through a coupled-quantum-dot interferometer
• Differential current noise as an identifier of Andreev bound states that induce nearly quantized conductance plateaus
• Spin Lifetimes in Quantum Dots from Noise Measurements
• Memory effect preserved time-local approach to noise spectrum of transport current

Cited by in corpus (1)

• Phase-controlled quantum transport signatures in a quantum dot-Majorana hybrid ring system