Related papers: Midgap spectrum of the fermion-vortex system
Most common types of symmetry breaking in quasi-one-dimensional electronic systems possess a combined manifold of states degenerate with respect to both the phase $\theta$ and the amplitude $A$ sign of the order parameter $A\exp(i\theta)$.…
The results of the mean field studies on the effects of the backward scattering with large momentum transfer in a two-dimensional electron system are extended to the case with various types of the Fermi surface and coupling constants. It is…
We study the zero energy modes that arise in an unusual vortex configuration involving both the kinetic energy and an appropriate mass term in a model which exhibits birefringent Dirac fermions as its low energy excitations. We find the…
It is shown that the mean-field description of a boson-fermion mixture with a dominating fermionic component, loaded in a one-dimensional optical lattice, is reduced to the nonlinear Schr\"{o}dinger equation with a periodic potential and…
The notion of a band gap is ubiquitous in the characterization of matter. Particularly interesting are pseudo-gaps, which are enigmatic regions of very low density of states that have been linked to novel phenomena like high temperature…
We study (multi) fermion - monopole bound states, many of which are the states that dyons adiabatically transition into as fermions become light. The properties of these bound states depend critically on the UV symmetries preserved by the…
We consider translation invariant quantum systems in thermodynamic limit. We argue that their energy-momentum spectra should have shapes consistent with effective models involving quasiparticles. Our main example is second quantized…
We theoretically analyze a quasi-two-dimensional system of fermionic polar molecules in a harmonic transverse confining potential. The renormalized energy bands are calculated by solving the Hartree-Fock equation numerically for various…
We theoretically study electronic states in graded-gap junctions of IV-VI compounds with band inversion. Using a two-band model within the ${\bf k}\cdot{\bf p}$ approximation and assuming that the gap and the gap centre present linear…
We argue that a consistent quantization of the Floreanini-Jackiw model, as a constrained system, should start by recognizing the improper nature of the constraints. Then each boundary conditon defines a problem which must be treated…
A quasi-1D superconductor with odd number of Fermi surfaces is expected to exhibit a nondegenerate Majorana bound state at the Fermi level at its boundary with an insulator (where the latter could be an actual insulator material or vacuum,…
We investigate a special class of the $\mathcal{PT}$-symmetric quantum models being perfectly invisible zero-gap systems with a unique bound state at the very edge of continuous spectrum of scattering states. The family includes the…
We develop an effective field theory to understand collective modes of a three-dimensional two-component Fermi superfluid with dipolar inter-particle interactions, which are modeled by an idealized separable potential. We first examine the…
The fermion mass spectrum is studied in the quenched approximation in the strong coupling vortex phase (VXS) of a globally U(1)$_L \otimes$U(1)$_R$ symmetric scalar-fermion model in two dimensions. In this phase fermion doublers can be…
We calculate the ground state current densities for 2+1 dimensional free fermion theories with local, translationally invariant boundary states. Deformations of the bulk wave functions close to the edge and boundary states both may cause…
We propose a new mechanism for stabilization of confined modes in lasers and semiconductor microcavities holding exciton-polariton condensates, with spatially uniform linear gain, cubic loss, and cubic self-focusing or defocusing…
Commensurability phenomena abound in nature and are typically associated with mismatched lengths, as can occur in quasiperiodic systems. However, not all commensuration effects are spatial in nature. In finite-sized Dirac systems, an…
The quantum-classical crossover from the Fermi liquid towards the Wigner solid is numerically revisited, considering small square lattice models where electrons interact via a Coulomb U/r potential. We review a series of exact numerical…
We investigate the structure of vortex-bound states in spin-singlet chiral superconductors with ($d_{x^2-y^2} \pm i d_{xy}$)-wave and ($d_{xz} \pm id_{yz}$)-wave pairing symmetries. It is found that vortices in the ($d_{xz} \pm…
We study theoretically the collective mode spectrum of a strongly imbalanced two-component unitary Fermi gas in a cigar-shaped trap, where the minority species forms a gas of polarons. We describe the collective breathing mode of the gas in…