We study low energy spin and charge transport through a 1D Mott-Hubbard insulator of finite length $L$ attached to Fermi liquid reservoirs characterized by different chemical potentials for electrons of opposite spin polarizations as it happens in quantum spin Hall insulators. We calculate the average currents (charge and spin) and their correlators and demonstrate how a transition induced by the reservoirs to the low energy Fermi liquid regime results in breakdown of the spin-charge separation, which is visible in the presence of the spin dependent voltages and a weak one electron scattering in the system. These calculations are carried out under assumption that the Hubbard gap 2M is large enough: $M > T_L \equiv v_c/L$ ( $v_c$ : charge velocity in the wire) and the scattering rate $Γ_s \ll T_L$ . Relation of these results to Kondo dot transport in the Toulouse limit is also clarified.We study low energy spin and charge transport through a 1D Mott-Hubbard insulator of finite length $L$ attached to Fermi liquid reservoirs characterized by different chemical potentials for electrons of opposite spin polarizations as it happens in quantum spin Hall insulators. We calculate the average currents (charge and spin) and their correlators and demonstrate how a transition induced by the reservoirs to the low energy Fermi liquid regime results in breakdown of the spin-charge separation, which is visible in the presence of the spin dependent voltages and a weak one electron scattering in the system. These calculations are carried out under assumption that the Hubbard gap 2M is large enough: $M > T_L \equiv v_c/L$ ($v_c$: charge velocity in the wire) and the scattering rate $Γ_s \ll T_L$. Relation of these results to Kondo dot transport in the Toulouse limit is also clarified.

arXiv:1105.3863May 19, 20110 citations

Local Density of States of One-Dimensional Mott Insulators and Charge-Density Wave States with a Boundary

Dirk Schuricht, Fabian H. L. Eßler, Akbar Jaefari +1 more

We determine the local density of states of one-dimensional incommensurate charge-density wave states in the presence of a strong impurity potential, which is modeled by a boundary. We find that the charge-density wave gets pinned at the impurity, which results in a singularity in the Fourier transform of the local density of states at momentum 2k_{F}. At energies above the spin gap we observe dispersing features associated with the spin and charge degrees of freedom, respectively. In the presence of an impurity magnetic field we observe the formation of a bound state localized at the impurity. All of our results carry over to the case of 1D Mott insulators by exchanging the roles of spin and charge degrees of freedom. We discuss the implications of our result for scanning tunneling microscopy experiments on spin-gap systems such as two-leg ladder cuprates.We determine the local density of states of one-dimensional incommensurate charge-density wave states in the presence of a strong impurity potential, which is modeled by a boundary. We find that the charge-density wave gets pinned at the impurity, which results in a singularity in the Fourier transform of the local density of states at momentum 2k_{F}. At energies above the spin gap we observe dispersing features associated with the spin and charge degrees of freedom, respectively. In the presence of an impurity magnetic field we observe the formation of a bound state localized at the impurity. All of our results carry over to the case of 1D Mott insulators by exchanging the roles of spin and charge degrees of freedom. We discuss the implications of our result for scanning tunneling microscopy experiments on spin-gap systems such as two-leg ladder cuprates.

arXiv:0802.1544Physical Review LettersAug 20, 200818 citations

Superexchange in Mott-Hubbard Insulators

Demetra Psiachos

arXiv:1407.3665Jul 14, 20140 citations

Renewed Understanding on Doped Mott Insulators

Masatoshi Imada

Bulletin of the American Physical SocietyMar 25, 20110 citations

Transport through a 1D Mott-Hubbard Insulator of Finite Length

Vadim V. Ponomarenko, Naoto Nagaosa

Transport through a 1D Mott-Hubbard insulator of a finite length $L$ is studied beyond the perturbative approach. At a special value of the low-energy constant of the interaction we have mapped the problem onto exactly solvable models and found current vs voltage at a high temperature $T>\mathrm{max}({m,T}_{L})$ and at a low energy $T,V<{T}_{L}$ ( ${T}_{L}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}v}_{c}/L$ ; ${v}_{c}$ : charge velocity). The result shows that for the strong interaction creating a large Mott-Hubbard gap $2m\ensuremath{\gg}{T}_{L}$ inside the wire, the transport is suppressed near half filling everywhere inside the gap except for a small region where $V,T<{T}_{L}\mathrm{exp}(\ensuremath{-}2m/{T}_{L})$.Transport through a 1D Mott-Hubbard insulator of a finite length $L$ is studied beyond the perturbative approach. At a special value of the low-energy constant of the interaction we have mapped the problem onto exactly solvable models and found current vs voltage at a high temperature $T>\mathrm{max}({m,T}_{L})$ and at a low energy $T,V<{T}_{L}$ ( ${T}_{L}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}v}_{c}/L$; ${v}_{c}$: charge velocity). The result shows that for the strong interaction creating a large Mott-Hubbard gap $2m\ensuremath{\gg}{T}_{L}$ inside the wire, the transport is suppressed near half filling everywhere inside the gap except for a small region where $V,T<{T}_{L}\mathrm{exp}(\ensuremath{-}2m/{T}_{L})$.

arXiv:cond-mat/9711167Physical Review LettersSep 14, 199816 citations

We study low energy spin and charge transport through a 1D Mott-Hubbard insulator of finite length

L

attached to Fermi liquid reservoirs characterized by different chemical potentials for electrons of opposite spin polarizations as it happens in quantum spin Hall insulators. We calculate the average currents (charge and spin) and their correlators and demonstrate how a transition induced by the reservoirs to the low energy Fermi liquid regime results in breakdown of the spin-charge separation, which is visible in the presence of the spin dependent voltages and a weak one electron scattering in the system. These calculations are carried out under assumption that the Hubbard gap 2M is large enough:

M > T_L \equiv v_c/L

(

v_c

: charge velocity in the wire) and the scattering rate

Γ_s \ll T_L

. Relation of these results to Kondo dot transport in the Toulouse limit is also clarified.

Transport through a 1D Mott-Hubbard insulator of a finite length

L

is studied beyond the perturbative approach. At a special value of the low-energy constant of the interaction we have mapped the problem onto exactly solvable models and found current vs voltage at a high temperature

T>\mathrm{max}({m,T}_{L})

and at a low energy

T,V<{T}_{L}

(

{T}_{L}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}v}_{c}/L

;

{v}_{c}

: charge velocity). The result shows that for the strong interaction creating a large Mott-Hubbard gap $2m\ensuremath{\gg}{T}_{L}$ inside the wire, the transport is suppressed near half filling everywhere inside the gap except for a small region where $V,T<{T}_{L}\mathrm{exp}(\ensuremath{-}2m/{T}_{L})$.