Generic model for current collapse in spin-blockaded transport

Muralidharan, Bhaskaran; Datta, Supriyo

doi:10.1103/physrevb.76.035432

Cited by 83 publications

(141 citation statements)

References 37 publications

Supporting

Mentioning

133

Contrasting

Order By: Relevance

“…Another recent study has attempted to establish conditions obeyed by the parameters involved, to observe a collapse in the current [95]. However, in our study, we find that some subtle changes in the parameters do result in NDR peaks in regimes where the conditions may not be followed strictly.…”

Section: Ndr In Double Quantum Dots In the Coulomb Blockade Regimecontrasting

confidence: 42%

Molecular Electronics: Effect of External Electric Field

2008

View full text Add to dashboard Cite

The effect of electric field, applied on systems in the nanoscale regime has attracted a lot of research in recent times. We highlight some of the recent results in the field of single molecule electronics and then move on to focus on some of our own results in this area.We have first shown how important it is to obtain the spatial profile of the external bias potential across the system, and how this would change in the presence of electron-electron interactions. We have also studied different kinds of insulators in the presence of the spatially varying external bias, and have explicitly shown that a two sublattice structure, caused either by a lattice distortion, or by the presence of substituents with strong dipolar nature, can result in negative differential resistance (NDR) in the transport characteristics. We also find this to be true in case of correlated insulators. Additionally, we have shown clear NDR behavior in a correlated double quantum dot by tuning the electron-electron interaction strength in the system.

show abstract

Section: Ndr In Double Quantum Dots In the Coulomb Blockade Regimecontrasting

confidence: 42%

Molecular Electronics: Effect of External Electric Field

2008

View full text Add to dashboard Cite

show abstract

“…The traditional semiconductor nanoelectronics also remains in front of modern research, in particular due to recent experiments with small quantum dots, where cotunneling effects were observed [45,46,47], as well as new rectification effects in double quantum dots, interpreted as spin blockade [48,49,50,51]. Note, that semiconductor experiments are very well controlled at present time, so they play an important role as a benchmark for the theory.…”

Section: Recent Experimentsmentioning

confidence: 99%

Green Function Techniques in the Treatment of Quantum Transport at the Molecular Scale

Ryndyk

Gutiérrez²,

Song

2009

Springer Series in Chemical Physics

View full text Add to dashboard Cite

The theoretical investigation of charge (and spin) transport at nanometer length scales requires the use of advanced and powerful techniques able to deal with the dynamical properties of the relevant physical systems, to explicitly include out-of-equilibrium situations typical for electrical/heat transport as well as to take into account interaction effects in a systematic way. Equilibrium Green function techniques and their extension to non-equilibrium situations via the Keldysh formalism build one of the pillars of current state-of-the-art approaches to quantum transport which have been implemented in both model Hamiltonian formulations and first-principle methodologies. In this chapter we offer a tutorial overview of the applications of Green functions to deal with some fundamental aspects of charge transport at the nanoscale, mainly focusing on applications to model Hamiltonian formulations.

show abstract

“…These parameters are calculated from the diagonalization of a tight-binding atomistic Hamiltonian [4][5][6]. The I-V characteristics are evaluated using the standard master equation scheme [2,3], by calculating the addition and removal transition rates ( Fig. 1c) and transition energies {ε ij } (Fig.…”

Section: Preliminariesmentioning

confidence: 99%

“…We find that this calculation is very successful in interpreting multiple NDRs in the spin blockade I-V characteristics. While the physics of multiple NDRs was discussed in an earlier work [3], we focus on the atomistic simulation of the DQD parameter set through atomistic NEMO 3-D simulations [4][5][6], and briefly summarize our transport results via rate equations. The DQD device considered here are made of AlGaAs-InGaAs-AlGaAs-InGaAs-AlGaAs layers that have been etched to vertical QD tower and side-gated to control the lateral confinement.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

NEMO-3D based atomistic simulation of a double quantum dot structure for spin-blockaded transport

et al. 2008

Self Cite

View full text Add to dashboard Cite

"NEMO-3D based atomistic simulation of a double quantum dot structure for spin-blockaded transport" (2008 Abstract This work combines an atomistic electronic structure calculation with many-body rate equations to simulate the current-voltage (I-V) characteristics of a weaklycoupled Double Quantum Dot (DQD) system in the spinblockade regime. Here we performed a NEMO-3D based, atomistic simulation of the geometry of the DQD to obtain its single electron eigen-states, hopping parameters, and Coulomb integrals followed by the evaluation of I-V characteristics with the many-electron spectrum of the DQD system, derived from this single-electron parameter set. The many-electron spectra and wave-functions are evaluated by exact-diagonalization of the many-electron system. The Hamiltonian is constructed from single electron eigenstates, hopping parameters and Coulomb integrals derived from atomistic NEMO 3-D simulations. Calculated I-V characteristics exhibit multiple regions of prominent Negative Differential Resistances (NDRs) that resemble the experimental trends. Unlike resonant tunnelling devices, however, level crossings in DQDs are negligible, and the NDRs result from a delicate interplay of delocalization, orbital offset and Coulomb interaction.

show abstract

Generic model for current collapse in spin-blockaded transport

Cited by 83 publications

References 37 publications

Molecular Electronics: Effect of External Electric Field

Molecular Electronics: Effect of External Electric Field

Green Function Techniques in the Treatment of Quantum Transport at the Molecular Scale

NEMO-3D based atomistic simulation of a double quantum dot structure for spin-blockaded transport

Contact Info

Product

Resources

About