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L I Glazman

Publications and source records attributed to L I Glazman.

11 recordsLinked to original sources
PubMed2006

Electronic Aharonov-Bohm effect induced by quantum vibrations.

Mechanical displacements of a nanoelectromechanical system shift the electron trajectories and hence perturb phase coherent charge transport through the device. We show theoretically that in the presence of a magnetic field such quantum-coherent displacements may give rise to an Aharonov-Bohm-type of effect. In particular, we demonstrate that quantum vibrations of a suspended carbon nanotube result in a positive nanotube magnetoresistance, which decreases slowly with the increase of temperature. This effect may enable one to detect quantum displacement fluctuations of a nanomechanical device.

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PubMed2006

Dynamic response of one-dimensional interacting fermions.

We evaluate the dynamic structure factor S(q, omega) of interacting one-dimensional spinless fermions with a nonlinear dispersion relation. The combined effect of the nonlinear dispersion and of the interactions leads to new universal features of S(q, omega). The sharp peak S(q, omega) approximately q(delta(omega -uq), characteristic for the Tomonaga-Luttinger model, broadens up; for a fixed becomes finite at arbitrarily large . The main spectral weight, however, is confined to a narrow frequency interval of the width deltaomega approximately q(2)/m. At the boundaries of this interval the structure factor exhibits power-law singularities with exponents depending on the interaction strength and on the wave number q.

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PubMed2003

Coulomb drag by small momentum transfer between quantum wires.

We demonstrate that in a wide range of temperatures Coulomb drag between two weakly coupled quantum wires is dominated by processes with a small interwire momentum transfer. Such processes, not accounted for in the conventional Luttinger liquid theory, cause drag only because the electron dispersion relation is not linear. The corresponding contribution to the drag resistance scales with temperature as T2 if the wires are identical, and as T5 if the wires are different.

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PubMed2003

Resonant tunneling of interacting electrons in a one-dimensional wire.

We consider the conductance of a one-dimensional wire interrupted by a double-barrier structure allowing for a resonant level. Using the electron-electron interaction strength as a small parameter, we are able to build a nonperturbative analytical theory of the conductance valid in a broad region of temperatures and for a variety of the barrier parameters. We find that the conductance may have a nonmonotonic crossover dependence on temperature, specific for a resonant tunneling in an interacting electron system.

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PubMed2003

Zeeman splitting of zero-bias anomaly in Luttinger liquids.

Tunneling density of states (DOS) in Luttinger liquid has a dip at zero energy, commonly known as the zero-bias anomaly. In the presence of a magnetic field, in addition to the zero-bias anomaly, the DOS develops two peaks separated from the origin by the Zeeman energy. We show that these finite-bias anomalies are characterized by a power-law behavior of the DOS and the differential conductance, and find the corresponding exponents at arbitrary strength of the electron-electron interaction. The developed theory is applicable to various kinds of quantum wires, including carbon nanotubes.

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PubMed2002

Persistent current in superconducting nanorings.

The superconductivity in very thin rings is suppressed by quantum phase slips. As a result, the amplitude of the persistent current oscillations with flux becomes exponentially small, and their shape changes from sawtooth to a sinusoidal one. We reduce the problem of low-energy properties of a superconducting nanoring to that of a quantum particle in a sinusoidal potential and show that the dependence of the current on the flux belongs to a one-parameter family of functions obtained by solving the respective Schrödinger equation with twisted boundary conditions.

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PubMed2001

Zero-bias anomaly in disordered wires.

We calculate the low-energy tunneling density of states nu(epsilon,T) of an N-channel disordered wire, taking into account the electron-electron interaction nonperturbatively. The finite scattering rate 1/tau results in a crossover from the Luttinger liquid behavior at higher energies, nu proportional to epsilon(alpha), to the exponential dependence nu(epsilon,T = 0) proportional to exp(-epsilon*/epsilon) at low energies, where epsilon* proportional to 1/(Ntau). At finite temperature T, the tunneling density of states depends on the energy through the dimensionless variable epsilon/root square[epsilon*T]. At the Fermi level nu(epsilon = 0,T)proportional to exp(-root square[epsilon*/T]).

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PubMed2001

Kondo effect in real quantum dots.

Exchange interaction within a quantum dot strongly affects the transport through it in the Kondo regime. In a striking difference with the results of the conventional model, where this interaction is neglected, here the temperature and magnetic field dependence of the conductance may become nonmonotonic: its initial increase follows by a drop when temperature and magnetic field are lowered.

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PubMed2001

Electron energy relaxation in the presence of magnetic impurities.

We study inelastic electron-electron scattering mediated by the exchange interaction of electrons with magnetic impurities and find the kernel of the corresponding two-particle collision integral. In a wide region of parameters, the kernel K is proportional to the inverse square of the transferred energy, K proportional to J4/E2. The exchange constant J is renormalized due to the Kondo effect. At small energy transfers, the 1/E2 divergence is cut off; the cutoff energy is determined by the dynamics of the impurity spins. The obtained results may provide a quantitative explanation of the experiments of Pothier et al. [Phys. Rev. Lett. 79, 3490 (1997)] on anomalously strong energy relaxation in short metallic wires.

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PubMed2000

Conduction through a quantum dot near a singlet-triplet transition.

Kondo effect in the vicinity of a singlet-triplet transition in a vertical quantum dot is considered. This system is shown to map onto a special version of the two-impurity Kondo model. At any value of the control parameter, the system has a Fermi-liquid ground state. Explicit expressions for the linear conductance as a function of the control parameter and temperature T are obtained. At T = 0, the conductance reaches the unitary limit approximately 4e(2)/h at the triplet side of the transition, and decreases with the increasing distance to the transition at the singlet side. At finite temperature, the conductance exhibits a peak near the transition point.

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