Interacting quantum dot coupled to a kondo spin: a universal Hamiltonian study.

Phys Rev Lett

Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA.

Published: April 2008

We study a Kondo spin coupled to a mesoscopic interacting quantum dot that is described by the "universal Hamiltonian." The problem is solved numerically by diagonalizing the system Hamiltonian in a good-spin basis and analytically in the weak and strong Kondo coupling limits. The ferromagnetic exchange interaction within the dot leads to a stepwise increase of the ground-state spin (Stoner staircase), which is modified nontrivially by the Kondo interaction. We find that the spin-transition steps move to lower values of the exchange coupling for weak Kondo interaction, but shift back up for sufficiently strong Kondo coupling. The interplay between Kondo and ferromagnetic exchange correlations can be probed with experimentally tunable parameters.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevLett.100.166601DOI Listing

Publication Analysis

Top Keywords

interacting quantum
8
quantum dot
8
kondo spin
8
strong kondo
8
kondo coupling
8
ferromagnetic exchange
8
kondo interaction
8
kondo
7
dot coupled
4
coupled kondo
4

Similar Publications

Ink disease caused by the hemibiotrophic root pathogen Phytophthora cinnamomi (Pc) is devastating for the European chestnut (Castanea sativa), unlike Asian chestnuts and interspecific hybrids which are resistant to Pc. The role that hormone responses play for Pc resistance remains little understood, especially regarding the temporal regulation of hormone responses. We explored the relationship between changes in tree health and physiology and alterations in leaf and root phytohormones and primary and secondary metabolites during compatible and incompatible Castanea spp.

View Article and Find Full Text PDF

Quantum crystallography methods have been employed to investigate complex formation between nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase (COX) enzymes, with particular focus on the COX-1 and COX-2 isoforms. This study analyzed the electrostatic interaction energies of selected NSAIDs (flurbiprofen, ibuprofen, meloxicam and celecoxib) with the active sites of COX-1 and COX-2, revealing significant differences in binding profiles. Flurbiprofen exhibited the strongest interactions with both COX-1 and COX-2, indicating its potent binding affinity.

View Article and Find Full Text PDF

This work represents a comprehensive study of the ground vibrational state of C-13 substituted methanol using very high-resolution far-infrared (FIR) and infrared (IR) Synchrotron Radiation spectra recorded with a very high signal-to-noise (S/N) ratio in the entire region from 40to5000cm, at the Canadian Light sources. High resolution combined with a high S/N ratio allowed the recording to be done with an unprecedented resolution of about 0.0017cm.

View Article and Find Full Text PDF

Emergence of opposing arrows of time in open quantum systems.

Sci Rep

January 2025

School of Mathematics and Physics, University of Surrey, GU2 7XH, Guildford, United Kingdom.

Deriving an arrow of time from time-reversal symmetric microscopic dynamics is a fundamental open problem in many areas of physics, ranging from cosmology, to particle physics, to thermodynamics and statistical mechanics. Here we focus on the derivation of the arrow of time in open quantum systems and study precisely how time-reversal symmetry is broken. This derivation involves the Markov approximation applied to a system interacting with an infinite heat bath.

View Article and Find Full Text PDF

A guidance to intelligent metamaterials and metamaterials intelligence.

Nat Commun

January 2025

ZJU-UIUC Institute, Interdisciplinary Center for Quantum Information, State Key Laboratory of Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, China.

The bidirectional interactions between metamaterials and artificial intelligence have recently attracted immense interest to motivate scientists to revisit respective communities, giving rise to the proliferation of intelligent metamaterials and metamaterials intelligence. Owning to the strong nonlinear fitting and generalization ability, artificial intelligence is poised to serve as a materials-savvy surrogate electromagnetic simulator and a high-speed computing nucleus that drives numerous self-driving metamaterial applications, such as invisibility cloak, imaging, detection, and wireless communication. In turn, metamaterials create a versatile electromagnetic manipulator for wave-based analogue computing to be complementary with conventional electronic computing.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!