Igor Kuzmenko

Kondo correlations and Majorana bound states in a metal to quantum-dot to topological-superconductor junction.

Electron transport through [normal metal]-[quantum dot]-[topological superconductor] junction is studied and reveals interlacing physics of Kondo correlations with two Majorana fermions bound state residing on the opposite edges of the topological superconductor. When the strength of the Majorana fermion coupling exceeds the temperature T , this combination of Kono-Majorana fermion physics can be observed: The usual peak of the temperature dependent zero biased conductance σ(V = 0, T ) splits and the conductance has a dip at T = 0. The height of the conductance side-peaks decreases with magnetic field.

Electronic excitations and correlations in quantum bars

Spectrum of boson fields and two-point correlators are analyzed in a quantum bar system (a superlattice formed by two crossed interacting arrays of quantum wires), with short range interwire interaction. The standard bosonization procedure is shown to be valid, within the two wave approximation. The system behaves as a sliding Luttinger liquid in the vicinity of the Gamma point, but its spectral and correlation characteristics have either 1D or 2D nature depending on the direction of the wave vector in the rest of the Brillouin zone. Due to interwire interaction, unperturbed states, propagating along the two arrays of wires, are always mixed, and the transverse components of the correlation functions do not vanish. This mixing is especially strong around the diagonal of the Brillouin zome, when tranverse correlators have the same order of magnitude as the longitudinal ones.The spectrum of boson fields and two-point correlators are analyzed in a quantum bar system (a superlattice formed by two crossed interacting arrays of quantum wires), with a short-range interwire interaction. The standard bosonization procedure is shown to be valid, within the two-wave approximation. The system behaves as a sliding Luttinger liquid in the vicinity of the Γ point, but its spectral and correlation characteristics have either 1D or 2D nature depending on the direction of the wave vector in the rest of the Brillouin zone. Due to the interwire interaction, unperturbed states propagating along the two arrays of wires are always mixed, and the transverse components of the correlation functions do not vanish. This mixing is especially strong around the diagonals of the Brillouin zone, where the transverse correlators have the same order of magnitude as the longitudinal ones.

Coqblin-Schrieffer model for an ultracold gas of ytterbium atoms with metastable state

Motivated by the impressive recent advance in manipulating cold ytterbium atoms we explore and substantiate the feasibility of realizing the Coqblin-Schrieffer model in a gas of cold fermionic

Model for overscreened Kondo effect in ultracold Fermi gas

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Infrared spectroscopy of quantum crossbars

Yb atoms. Making use of different AC polarizabillity of the electronic ground state (electronic configuration

Spectrum, correlations and dimensional crossover in triple 2D quantum crossbars

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Kondo tunneling into a quantum spin Hall insulator

) and the long lived metastable state (electronic configuration

Ultraviolet probing of quantum crossbars

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Quantum Crossbars: Spectra and Spectroscopy

), it is substantiated that the latter can be localized and serve as a magnetic impurity while the former remains itinerant. The exchange mechanism between the itinerant

Dimensional Crossover in 2D Crossbars

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