We consider chiral electrons moving along the one-dimensional helical edge of a two-dimensional topological insulator and interacting with disordered chain Kondo impurities. Assuming electron-spin couplings random anisotropies, we map this system to problem pinning charge density wave by potential. This mapping proves that arbitrary weak anisotropic disorder in coupling spin impurities leads Anderson localization states.

We analyze the effect of electron-electron interaction on resistivity a metal near Pomeranchuk quantum phase transition (QPT). show that umklapp processes are not effective QPT, and one must consider both interactions disorder to obtain finite T dependent resistivity. By power counting, correction residual at low scales as AT((D+2)/3) Z=3 QPT. show, however, A=0 for simply connected, convex Fermi surface in 2D, due hidden integrability electron motion. argue A>0 two-band (s-d) model propose...

While it is well-known that the electron-electron (ee) interaction cannot affect resistivity of a Galilean-invariant Fermi liquid (FL), reverse statement not necessarily true: non-Galilean-invariant FL does follow T 2 behavior. The behavior guaranteed only if Umklapp processes are allowed; however, surface (FS) small or very long range, Umklapps suppressed. In this case, term can result from combined – but distinct quantum-interference corrections effect electron-impurity and ee...

Charge transport in doped quantum paraelectrics (QPs) presents a number of puzzles, including pronounced ${T}^{2}$ regime the resistivity. We analyze charge QP within model electrons coupled to soft transverse optical (TO) mode via two-phonon mechanism. For $T$ above soft-mode frequency but below some characteristic scale (${E}_{0}$), resistivity scales with occupation phonons squared, i.e., as ${T}^{2}$. The scattering rate does not depend on carrier density and is affected by crossover...

The authors have considered in the framework of field-theoretical approach asymptotics random walks media with quenched disorder which is described by drift velocity field V(x) subjected to various constraints. has proved be relevant d<or=2 dimensions leading (at d=2) superdiffusion behaviour for solenoidal ( delta Vi/ xi=0) and subdiffusion potential drifts xj- Vj/ xi=0).

We study multiphoton scattering inside a one-dimensional waveguide caused by number of resonant two-level atoms located in region small compared to the photon wavelength. Applying powerful methods theory integrable quantum systems, we analyze correlations scattering. In particular, for important case two-photon scattering, describe explicitly dependence parameters on atoms. Also, outline method describing an arbitrary photons and present explicit expressions three effective chiral model. The...

A system of two identical atoms sharing a photon with high-$Q$ resonator mode is studied by nonperturbative formalism. As opposed to previously considered models, here the interatom coupling shown result from competing effects vacuum Rabi splitting and exchange via off-resonant modes. Strong suppression excitation transfer predicted at both near- far-zone separations.

Action of an external high-frequency electromagnetic field on free electrons in normal-metal mesoscopic rings threaded by a static magnetic flux is shown to lead direct current proportional the intensity. The disorder-averaged value periodic function and may considerably exceed corresponding equilibrium persistent current.

For a system of two spatially separated qubits (two-level atoms) coupled to one-dimensional waveguide we have described the time evolution singly or doubly excited states atomic subsystem. When interatomic distance $l$ takes special (``resonant'' ``antiresonant'') values, resonant atoms can form metastable (dark) states. If slightly deviates from one values frequencies do not coincide, dark slowly decay and calculated rate. Also, found that state located at positions does completely but,...

While it is well-known that the electron-electron (\emph{ee}) interaction cannot affect resistivity of a Galilean-invariant Fermi liquid (FL), reverse statement not necessarily true: non-Galilean-invariant FL does follow T^2 behavior. The behavior guaranteed only if Umklapp processes are allowed; however, surface (FS) small or very long range, Umklapps suppressed. In this case, term can result from combined--but distinct quantum-interference corrections-- effect electron-impurity and...

We show that the paradigmatic Ruderman-Kittel-Kasuya-Yosida (RKKY) description of two local magnetic moments coupled to propagating electrons breaks down in helical Luttinger Liquids when electron interaction is stronger than some critical value. In this novel regime, Kondo effect overwhelms RKKY over all macroscopic inter-impurity distances. This phenomenon a direct consequence helicity (realized, for instance, at edges time-reversal invariant topological insulator) and does not take place...

We have studied low-temperature properties of interacting electrons in a one-dimensional quantum wire (Luttinger liquid) side-hybridized with single-level impurity. The hybridization induces backscattering the which strongly affects its low-energy properties. Using one-loop renormalization group approach valid for weak electron-electron interaction, we calculated transmission coefficient through wire, $\mathcal{T}(\ensuremath{\epsilon})$, and local density states,...

We study the effect of electron-electron interaction on surface resistivity three-dimensional (3D) topological insulators Bi${}_{2}$Te${}_{3}$ family. In absence umklapp scattering, existence Fermi-liquid (${T}^{2}$) term in a two-dimensional (2D) metal depends Fermi geometry, particular, whether it is convex or concave. On doping, 2D metallic states 3D family changes its shape from to concave due hexagonal warping, while still being too small allow for scattering. show that ${T}^{2}$...

We consider the optical conductivity of a clean two-dimensional metal near quantum spin-density-wave transition. Critical magnetic fluctuations are known to destroy fermionic coherence at "hot spots" Fermi surface but coherent quasiparticles survive in rest surface. A large part is not really "cold" rather "lukewarm" sense that strongly renormalized compared non-interacting case. discuss self-energy lukewarm fermions and their contribution conductivity, $\sigma(\Omega)$, focusing...

In the case of disordered nonlinear media, it is shown that in four-wave mixing a phenomena analogous to phase conjugation may occur. contrast transparent media which two counterpropagating pump waves (with frequency ${\ensuremath{\omega}}_{p}$) are required, occur presence single wave injected into material. We find angular distribution radiation ${\ensuremath{\omega}}_{s}$ (${\ensuremath{\omega}}_{s}$=2${\ensuremath{\omega}}_{p}$-${\ensuremath{\omega}}_{i}$, where...