Quantum engineering of Majorana quasiparticles in one-dimensional optical lattices

Ptok, Andrzej; Cichy, Agnieszka; Domański, T.

doi:10.1088/1361-648x/aad659

Cited by 13 publications

(13 citation statements)

References 114 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This system requires a meticulously made nanowire [67], because any disorder has destructive role on the topological phase [47,[68][69][70][71]. However, local impurity can lead to MBS separation into the pair of new MBS at the newly created boundaries of the homogeneous system in topological states [66,[72][73][74][75].…”

Section: Basic Propertiesmentioning

confidence: 99%

Controlling the bound states in a quantum-dot hybrid nanowire

2017

Self Cite

View full text Add to dashboard Cite

Recent experiments using the quantum dot coupled to the topological superconducting nanowire [M.T. Deng et al., Science 354, 1557] revealed that zero-energy bound state coalesces from the Andreev bound states. Such quasiparticle states, present in the quantum dot, can be controlled by the magnetic and electrostatic means. We use microscopic model of the quantum-dot-nanowire structure to reproduce the experimental results, applying the Bogoliubov-de Gennes technique. This is done by studying the gate voltage dependence of the various types of bound states and mutual influence between them. We show that the zero energy bound states can emerge from the Andreev bound states in topologically trivial phase and can be controlled using various means. In non-trivial topological phase we show the possible resonance between this zero energy levels with Majorana bound states. We discuss and explain this phenomena as a result of dominant spin character of discussed bound states. Presented results can be applied in experimental studies by using the proposed nanodevice.

show abstract

Section: Basic Propertiesmentioning

confidence: 99%

Controlling the bound states in a quantum-dot hybrid nanowire

2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, self-energy corrections may be neglected since they do not affect the quasiparticle states near zero energy [86]. Moreover, in ultracold-atom setups, the superconducting term depends on the quasiparticle densities, and in that case the corresponding Bogoliubov-de Gennes equations needs to be solved self-consistently [42][43][44][45].…”

Section: A Hamiltonianmentioning

confidence: 99%

“…Their nonabelian exchange statistics [1,18,19] may lead to the realization of fault-tolerant quantum computation [20][21][22][23][24][25][26][27]. 1D topological superconductivity can be realized in Majorana nanowires, i.e., proximitized semiconducting nanowires with strong spinorbit coupling and broken time-reversal symmetry [4][5][6][7][8][9][10][11][12][13][14][15][16][17], in epitaxial 1D semiconductor-superconductor heterostructures [28][29][30], arrays of magnetic atoms deposited on a conventional superconductor [31][32][33][34][35][36][37][38][39][40][41], or optically-trapped ultracold fermionic atoms coupled to a molecular BEC cloud [42][43][44][45].…”

Section: Introductionmentioning

confidence: 99%

Majorana/Andreev crossover and the fate of the topological phase transition in inhomogeneous nanowires

Marra,

Nigro

2021

Preprint

View full text Add to dashboard Cite

Majorana bound states (MBS) and Andreev bound states (ABS) in realistic Majorana nanowires setups have similar experimental signatures which make them hard to distinguishing one from the other. Here, we characterize the continuous Majorana/Andreev crossover interpolating between fully-separated, partially-separated, and fully-overlapping Majorana modes, in terms of global and local topological invariants, fermion parity, quasiparticle densities, Majorana pseudospin and spin polarizations, density overlaps and transition probabilities between opposite Majorana components. We found that in inhomogeneous wires, the transition between fullyoverlapping trivial ABS and nontrivial MBS does not necessarily mandate the closing of the bulk gap of quasiparticle excitations, but a simple parity crossing of partially-separated Majorana modes (ps-MM) from trivial to nontrivial regimes. We demonstrate that fully-separated and fully-overlapping Majorana modes correspond to the two limiting cases at the opposite sides of a continuous crossover: the only distinction between the two can be obtained by estimating the degree of separations of the Majorana components. This result does not contradict the bulk-edge correspondence: Indeed, the field inhomogeneities driving the Majorana/Andreev crossover have a length scale comparable with the nanowire length, and therefore correspond to a nonlocal perturbation which breaks the topological protection of the MBS.

show abstract

“…In our system, the value of the chemical potential varies from site to site i.e., µ i = µ + V i . This non-homogeneity can lead to a situation in which the above condition is met only locally [32][33][34]. We can therefore construct a space dependent indicator [35] that describes the spatial distribution of the non-trivial topological phase,…”

Section: Non-trivial Topological Domains and Topological Phase Diagrammentioning

confidence: 99%

Probing the chirality of 1D Majorana edge states around a 2D nanoflake in a superconductor

Ptok,

Alspaugh,

Głodzik

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

The interplay between superconductivity, magnetic field and spin-orbit coupling can lead to the realization of non-trivial topological phases. Recent experiments have found signatures of such phases in magnetic nanoflakes formed by nanostructures coupled to a superconducting substrate. These heterostructures comprise a topologically non-trivial region surrounded by a trivial one due to the finite magnetic exchange field induced by the magnetic nanoflake. The analysis of the topological phase diagram of such a system shows that a similar phase separation occurs by tuning the chemical potential of the nanoflake. In this paper, we study such a possibility in detail, analyzing the spatial extent of the edge modes circulating around the nanoflake and discussing some practical implementations. We also show how the chirality of Majorana edge states can be probed using scanning tunneling spectroscopy with a double tip setup.

show abstract

Quantum engineering of Majorana quasiparticles in one-dimensional optical lattices

Cited by 13 publications

References 114 publications

Controlling the bound states in a quantum-dot hybrid nanowire

Controlling the bound states in a quantum-dot hybrid nanowire

Majorana/Andreev crossover and the fate of the topological phase transition in inhomogeneous nanowires

Probing the chirality of 1D Majorana edge states around a 2D nanoflake in a superconductor

Contact Info

Product

Resources

About