Herbert Schoeller

Strong Tunneling in Small Quantum Dots: Kondo Effect in Two Model Systems (2007)

We study a generic problem of dissipative quantum mechanics, a small local quantum system with discrete states coupled in an arbitrary way (i.e. not necessarily linear) to several infinitely large...

Teemu Pohjola, Daniel Boese, Jürgen König, Herbert Schoeller, Gerd Schön

INTRODUCTION Electron transport through small quantum dots is strongly affected by three energy scales: the charging energy EC , the single-electron level spacing ffi (typically ffi ! EC ), and the...

Transport Through Quantum Dots And The Kondo Problem (2007)

Jürgen König, J Urgen, K Onig, Teemu Pohjola, Herbert Schoeller

. Transport through quantum dots with large level spacing and charging energy is considered. At low temperature and strong coupling to the leads, quantum fluctuations and the Kondo effect become...

Zero-bias anomalies and boson-assisted tunneling through quantum dots. (2007)

Aharonov-Bohm oscillations of electrical and thermal properties of a quantum dot ring geometry. (2007)

Blanter, Ya.M., Bruder, Christoph, Fazio, Rosario, Schoeller, Herbert

Transport theory of interacting quantum dots. (2007)

Cotunneling at resonance for the single-electron transistor. (2007)

Aharonov-Bohm-type oscillations of thermopower in a quantum dot ring geometry. (2007)

Blanter, Ya.M., Bruder, Christoph, Fazio, Rosario, Schoeller, Herbert

Photon-assisted transport through ultrasmall quantum dots: influence of intradot transitions. (2007)

Strong electron tunneling through mesoscopic metallic grains. (2007)

Golubev, D.S., Koenig, Jürgen, Schoeller, Herbert, Schoen, Gerd, Zaikin, Andrei D.

Photon-assisted transport through a double quantum dot with a time-dependent interdot barrier. (2007)

Resonant tunneling and Coulomb oscillations. (2007)

Transport Theorie für wechselwirkende Quantenpunkte. (2007)

Resonant tunneling through a two-level dot and double quantum dots (2007)

Pohjola, T., Koenig, Jürgen, Salomaa, M., Schmid, J., Schoeller, Herbert, Schoen, Gerd

Real-time renormalization group and cutoff scales in nonequilibrium applied to an arbitrary quantum dot in the Coulomb blockade regime (2007)

Korb, Thomas, Reininghaus, Frank, Schoeller, Herbert, König, Jürgen

We apply the real-time renormalization group (RG) in nonequilibrium to an arbitrary quantum dot in the Coulomb blockade regime. Within one-loop RG-equations, we include self-consistently the kernel...

Nonequilibrium functional renormalization group for interacting quantum systems (2007)

Jakobs, Severin G., Meden, Volker, Schoeller, Herbert

We propose a nonequilibrium version of functional renormalization within the Keldysh formalism by introducing a complex valued flow parameter in the Fermi or Bose functions of each reservoir. Our...

Temperature induced phase averaging in one-dimensional mesoscopic systems (2006)

Jakobs, Severin G., Meden, Volker, Schoeller, Herbert, Enss, Tilman

We analyse phase averaging in one-dimensional interacting mesoscopic systems with several barriers and show that for incommensurate positions an independent average over several phases can be induced...

Fingerprints of the Magnetic Polaron in Nonequilibrium Electron Transport through a Quantum Wire Coupled to a Ferromagnetic Spin Chain (2006)

Reininghaus, Frank, Korb, Thomas, Schoeller, Herbert

We study nonequilibrium quantum transport through a mesoscopic wire coupled via local exchange to a ferromagnetic spin chain. Using the Keldysh formalism in the self-consistent Born approximation, we...

Magnon transport and spin current switching through quantum dots (2005)

Strelcyk, Olaf, Korb, Thomas, Schoeller, Herbert

We study the nonequilibrium spin current through a quantum dot consisting of two localized spin-1/2 coupled to two ferromagnetic insulators. The influence of an intra-dot magnetic field and exchange...

Designable electron transport features in one-dimensional arrays of metallic nanoparticles: Monte Carlo study of the relation between shape and transport (2005)

Semrau, Stefan, Schoeller, Herbert, Wenzel, Wolfgang

We study the current and shot noise in a linear array of metallic nanoparticles taking explicitly into consideration their discrete electronic spectra. Phonon assisted tunneling and dissipative...

Nonperturbative analysis of coupled quantum dots in a phonon bath (2002)

Keil, Markus, Schoeller, Herbert

Transport through coupled quantum dots in a phonon bath is studied using the recently developed real-time renormalization-group method. Thereby, the problem can be treated beyond perturbation theory...

Spin accumulation in ferromagnetic single-electron transistors in the cotunneling regime (2002)

Martinek, Jan, Barnas, Józef, Maekawa, Sadamichi, Schoeller, Herbert, Schön, Gerd

We propose a new method of direct detection of spin accumulation, which overcomes problems of previous measurement schemes. A spin dependent current in a single-electron transistor with ferromagnetic...

Quantum Phase Transition in a Multi-Level Dot (2001)

Hofstetter, Walter, Schoeller, Herbert

We discuss electronic transport through a lateral quantum dot close to the singlet-triplet degeneracy in the case of a single conduction channel per lead. By applying the Numerical Renormalization...

Kondo Correlations and the Fano Effect in Closed AB-Interferometers (2001)

Hofstetter, Walter, König, Jürgen, Schoeller, Herbert

We study the Fano-Kondo effect in a closed Aharonov-Bohm (AB) interferometer which contains a single-level quantum dot and predict a frequency doubling of the AB oscillations as a signature of...

Kondo Correlations and the Fano Effect in Closed Aharonov-Bohm Interferometers (2001)

Hofstetter, Walter, König, Jürgen, Schoeller, Herbert

Influence of nano-mechanical properties on single electron tunneling: A vibrating Single-Electron Transistor (2000)

Boese, Daniel, Schoeller, Herbert

We describe single electron tunneling through molecular structures under the influence of nano-mechanical excitations. We develop a full quantum mechanical model, which includes charging effects and...

Non-Linear Transport through a Molecular Nanojunction (2000)

Hettler, Matthias H., Schoeller, Herbert, Wenzel, Wolfgang

We present a simple model of electrical transport through a metal-molecule-metal nanojunction that includes charging effects as well as aspects of the electronic structure of the molecule. The...

Real-Time-RG Analysis of the Dynamics of the Spin-Boson Model (2000)

Keil, Markus, Schoeller, Herbert

Using a real-time renormalization group method we determine the complete dynamics of the spin-boson model with ohmic dissipation for coupling strengths $\alpha\lesssim 0.1-0.2$. We calculate the...

Interference and interaction effects in multi-level quantum dots (2000)

Boese, Daniel, Hofstetter, Walter, Schoeller, Herbert

Using renormalization group techniques, we study spectral and transport properties of a spinless interacting quantum dot consisting of two levels coupled to metallic reservoirs. For strong Coulomb...

Orbital and spin Kondo effects in a double quantum dot (2000)

Pohjola, Teemu, Schoeller, Herbert, Schön, Gerd

Motivated by recent experiments, in which the Kondo effect has been observed for the first time in a double quantum-dot structure, we study electron transport through a system consisting of two...

Spin dynamics of Mn12-acetate in the thermally-activated tunneling regime: ac-susceptibility and magnetization relaxation (2000)

Pohjola, Teemu, Schoeller, Herbert

In this work, we study the spin dynamics of Mn12-acetate molecules in the regime of thermally assisted tunneling. In particular, we describe the system in the presence of a strong transverse magnetic...

Renormalization group study of the 1d polaron problem (2000)

Keil, Markus, Schoeller, Herbert

We investigate the one-dimensional polaron problem and calculate the ground state energy and the effective mass. We use a real-time renormalization group method and compare our results with first and...

An introduction to real-time renormalization group (1999)

Real-time renormalization group and charge fluctuations in quantum dots (1999)

This article presents a tutorial introduction to a recently developed real-time renormalization group method. It describes nonequilibrium properties of discrete quantum systems coupled linearly to an...

Schoeller, Herbert, König, Jürgen

We develop a perturbative renormalization-group method in real time to describe nonequilibrium properties of discrete quantum systems coupled linearly to an environment. We include energy broadening...

Resonant Tunneling through Quantum Dots (1999)

Teemu Pohjola, Daniel Boese, Herbert Schoeller, Jürgen König, Gerd Schön

Motivated by recent experiments we analyse a new setup of capacitively coupled semiconductor quantum dots. We identify a region where Kondo-assisted tunneling should be observable. We find an...

Strong Tunneling in Double-Island Structures (1998)

Pohjola, Teemu, König, Jürgen, Schoeller, Herbert, Schön, Gerd

We study the electron transport through a system of two low-capacitance metal islands connected in series between two electrodes. The work is motivated in part by experiments on semiconducting...

Strong Tunneling in the Single-Electron Box (1998)

König, Jürgen, Schoeller, Herbert

We study strong tunneling (i.e. transmission $h/e^2R_T \gg 1$) in the single-electron box with many transverse modes at zero temperature. We develop a new renormalization group method which includes...

Bosonization for Beginners --- Refermionization for Experts (1998)

Von Delft, Jan, Schoeller, Herbert

This tutorial gives an elementary and self-contained review of abelian bosonization in 1 dimension in a system of finite size $L$, following and simplifying Haldane's constructive approach. As a...

Observing the Berry phase in diffusive conductors: Necessary conditions for adiabaticity (1998)

Loss, Daniel, Schoeller, Herbert, Goldbart, Paul M.

In a recent preprint (cond-mat/9803170), van~Langen, Knops, Paasschens and Beenakker attempt to re-analyze the proposal of Loss, Schoeller and Goldbart (LSG) [Phys. Rev. B~48, 15218 (1993)]...

Cotunneling and renormalization effects for the single-electron transistor (1998)

Cotunneling at resonance for the single-electron transistor (1997)

We study electron transport through a small metallic island in the perturbative regime. Using a diagrammatic real-time technique, we calculate the occupation of the island as well as the conductance...

Strong Electron Tunneling through Mesoscopic Metallic Grains (1997)

We study electron transport through a small metallic island in the perturbative regime. Using a recently developed diagrammatic technique, we calculate the occupation of the island as well as the...

Golubev, D. S., König, Jürgen, Schoeller, Herbert, Schön, Gerd, Zaikin, A. D.

We describe electron transport through small metallic grains with Coulomb blockade effects beyond the perturbative regime. For this purpose we study the real-time evolution of the reduced density...

Transport Theorie für wechselwirkende Quantenpunkte. (1997)

Transport theory of interacting quantum dots. (1997)

Cotunneling at resonance for the single-electron transistor. (1997)

Aharonov-Bohm-type oscillations of thermopower in a quantum dot ring geometry. (1997)

Blanter, Ya.M., Bruder, Christoph, Fazio, Rosario, Schoeller, Herbert

Photon-assisted transport through ultrasmall quantum dots: influence of intradot transitions. (1997)

Strong electron tunneling through mesoscopic metallic grains. (1997)

Golubev, D.S., Koenig, Jürgen, Schoeller, Herbert, Schoen, Gerd, Zaikin, Andrei D.

Photon-assisted transport through a double quantum dot with a time-dependent interdot barrier. (1997)

Resonant tunneling through a two-level dot and double quantum dots. (1997)

Pohjola, T., Koenig, Jürgen, Salomaa, M., Schmid, J., Schoeller, Herbert, Schoen, Gerd

Aharonov-Bohm-Type Oscillations of Thermopower in a Quantum Dot Ring Geometry (1996)

Blanter, Ya. M., Bruder, C., Fazio, Rosario, Schoeller, Herbert

We investigate Aharonov-Bohm-type oscillations of the thermopower of a quantum dot embedded in a ring for the case when the interaction between electrons can be neglected. The thermopower is shown to...

RKKY interaction and Kondo screening cloud for correlated electrons (1996)

Egger, Reinhold, Schoeller, Herbert

The RKKY law and the Kondo screening cloud around a magnetic impurity are investigated for correlated electrons in 1D (Luttinger liquid). We find slow algebraic distance dependences, with a crossover...

Resonant tunneling through ultrasmall quantum dots: zero-bias anomalies, magnetic field dependence, and boson-assisted transport (1996)

König, Jürgen, Schmid, Jörg, Schoeller, Herbert, Schön, Gerd

We study resonant tunneling through a single-level quantum dot in the presence of strong Coulomb repulsion beyond the perturbative regime. The level is either spin-degenerate or can be split by a...

Zero-bias anomalies and boson-assisted tunneling through quantum dots. (1996)

Aharonov-Bohm oscillations of electrical and thermal properties of a quantum dot ring geometry. (1996)

Blanter, Ya.M., Bruder, Christoph, Fazio, Rosario, Schoeller, Herbert

Aharonov-Bohm oscillations and resonant tunneling in strongly correlated quantum dots (1995)

Bruder, C., Fazio, Rosario, Schoeller, Herbert

We investigate Aharonov-Bohm oscillations of the current through a strongly correlated quantum dot embedded in an arbitrary scattering geometry. Resonant-tunneling processes lead to a flux-dependent...

Zero-bias anomalies and boson-assisted tunneling through quantum dots (1995)

Resonant Tunneling and Coulomb Oscillations (1995)

We study resonant tunneling through a quantum dot with one degenerate level in the presence of a strong Coulomb repulsion and a bosonic environment. Using a real-time approach we calculate the...

Resonant Tunneling and Charging Effects, a Path Integral Approach (1995)

The influence of quantum fluctuations on electron transport through small metallic islands with Coulomb blockade effects is studied beyond the perturbative regime. In tunnel junctions with low...

König, Jürgen, Schoeller, Herbert, Schön, Gerd, Fazio, Rosario

Electron tunneling through small metallic islands with low capacitance is studied. The large charging energy in these systems is responsible for nonperturbative Coulomb blockade effects. We further...

Resonant tunneling and Coulomb oscillations. (1995)