16 research outputs found
Finite frequency noise in chiral Luttinger liquid coupled to phonons
We study transport between Quantum Hall (QH) edge states at filling factor
in the presence of electron-acoustic-phonon coupling. Performing a
Bogoliubov-Valatin (BV) trasformation the low-energy spectrum of interacting
electron-phonon system is presented. The electron-phonon interaction splits the
spectrum into charged and neutral "downstream" and neutral "upstream" modes
with different velocities. In the regimes of dc and periodic ac biases the
tunelling current and non-equilibrium finite frequency non-symmetrized noise
are calculated perturbatively in tunneling coupling of quantum point contact
(QPC). We show that the presence of electron-phonon interaction strongly
modifies noise and current relations compared to free-fermion case
Current correlations of Cooper-pair tunneling into a quantum Hall system
We study Cooper pair transport through a quantum point contact between a
superconductor and a quantum Hall edge state at integer and fractional filling
factors. We calculate the tunnelling current and its finite-frequency noise to
the leading order in the tunneling amplitude for dc and ac bias voltage in the
limit of low temperatures. At zero temperature and in case of tunnelling into a
single edge channel both the conductance and differential shot noise vanish as
a result of Pauli exclusion principle. In contrast, in the presence of two edge
channels, this Pauli blockade is softened and a non-zero conductance and shot
noise are revealed
Hydrodynamic Navier-Stokes equations in two-dimensional systems with Rashba spin-orbit coupling
We study a two-dimensional (2D) electron system with a linear spectrum in the
presence of Rashba spin-orbit (RSO) coupling in the hydrodynamic regime. We
derive a semiclassical Boltzmann equation with a collision integral due to
Coulomb interactions in the basis of the eigenstates of the system with RSO
coupling. Using the local equilibrium distribution functions, we obtain a
generalized hydrodynamic Navier-Stokes equation for electronic systems with RSO
coupling. In particular, we discuss the influence of the spin-orbit coupling on
the viscosity and the enthalpy of the system and present some of its observable
effects in hydrodynamic transport.Comment: 15 pages, 2 figures, to be submitted for the special issue on
electron hydrodynamics in Low Temperature Physic
Overlap of parafermionic zero modes at a finite distance
Parafermion bound states (PBSs) are generalizations of Majorana bound states (MBSs) and have been predicted to exist as zero-energy eigenstates in proximitized fractional quantum Hall edge states. Similarly to MBSs, a finite distance between the PBS can split the ground state degeneracy. However, parafermionic modes have a richer exchange statistics than MBSs, so several interaction terms are allowed by the underlying symmetry, rendering the effective Hamiltonian governing a pair of PBSs at a finite distance nontrivial. Here, we use a combination of analytical techniques (semiclassical instanton approximation) and numerical techniques (quantum Monte Carlo simulations) to determine the effective coupling Hamiltonian. For this purpose, we go beyond the dilute one-instanton gas approximation and show how finite-size effects can give rise to higher-order parafermion interactions. We find excellent agreement between the analytical results and Monte Carlo simulations. We estimate that these finite-size corrections should be observable in some of the recently proposed experiments to observe PBSs in strongly correlated systems