We solve the Schrödinger equation for an interacting spin chain locally coupled to a quantum environment with a specific degeneracy structure. The reduced dynamics of the whole spin chain as well as of single spins is analyzed. We show that the total spin chain relaxes to a thermal equilibrium state independently of the internal interaction strength. In contrast, the asymptotic states of each individual spin are thermal for weak but nonthermal for stronger spin-spin coupling. The transition between both scenarios is found for couplings of the order of 0.1 x deltaE , with deltaE denoting the Zeeman splitting. We compare these results with a master-equation treatment; when time averaged, both approaches lead to the same asymptotic state and finally with analytical results.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevE.72.026104 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Exploring the Gating Mechanism of the Human Copper Transporter, hCtr1, Using EPR Spectroscopy.
Biomolecules
January 2025
Department of Chemistry and Institute of Nanotechnology and Advanced Materials, Faculty of Exact Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
Ctr1 is a membrane-spanning homotrimer that facilitates copper uptake in eukaryotic cells with high affinity. While structural details of the transmembrane domain of human Ctr1 have been elucidated using X-ray crystallography and cryo-EM, the transfer mechanisms of copper and the conformational changes that control the gating mechanism remain poorly understood. The role of the extracellular N-terminal domains is particularly unclear due to the absence of a high-resolution structure of the full-length hCtr1 protein and limited biochemical and biophysical characterization of the transporter in solution and in cell.
View Article and Find Full Text PDFSpray-Printed Light-Emitting Diodes with Perovskite/Polymer Composite Emitters on Various Transparent Substrates.
ACS Appl Mater Interfaces
January 2025
Department of Chemical and Biological Engineering, Sookmyung Women's University, Seoul 04310, Korea.
Advancements in printing techniques are essential for fabricating next-generation displays. Lead halide perovskites demonstrate great potential as light emitters of solution-processed light-emitting diodes (LEDs). In particular, the perovskite/polymer composite emitters exhibit exceptional luminescent characteristics, mechanical flexibility, and environmental stability due to the improved film morphologies and defect passivation achieved through the introduction of polymer additives.
View Article and Find Full Text PDFReview of honeycomb-based Kitaev materials with zigzag magnetic ordering.
Acta Crystallogr B Struct Sci Cryst Eng Mater
February 2025
Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
The search for a Kitaev quantum spin liquid in crystalline magnetic materials has fueled intense interest in the two-dimensional honeycomb systems. Many promising candidate Kitaev systems are characterized by a long-range-ordered magnetic structure with an antiferromagnetic zigzag-type order, where the static moments form alternating ferromagnetic chains. Recent experiments on high-quality single crystals uncovered the existence of intriguing multi-k magnetic structures, which evolved from zigzag structures.
View Article and Find Full Text PDFSpin Chains with Highly Quantum Character through Strong Covalency in CaCrN.
J Am Chem Soc
January 2025
Materials Department, University of California, Santa Barbara, Santa Barbara, California 93106, United States.
The insulating transition metal nitride CaCrN consists of sheets of triangular [CrN] units with symmetry that are connected via quasi-1D zigzag chains. Due to strong covalency between Cr and N, Cr ions are unusually low-spin, and = 1/2. Magnetic susceptibility measurements reveal dominant quasi-1D spin correlations with very large nearest-neighbor antiferromagnetic exchange = 340 K and yet no sign of magnetic order down to = 0.
View Article and Find Full Text PDFSelf-Diffusion of Star and Linear Polyelectrolytes in Salt-Free and Salt Solutions.
Macromolecules
January 2025
Department of Materials Science & Engineering, Texas A&M University, College Station, Texas 77840, United States.
This work explored solution properties of linear and star poly(methacrylic acids) with four, six, and eight arms (PMAA, 4PMAA, PMAA, and 8PMAA, respectively) of matched molecular weights in a wide range of pH, salt, and polymer concentrations. Experimental measurements of self-diffusion were performed by fluorescence correlation spectroscopy (FCS), and the results were interpreted using the scaling theory of polyelectrolyte solutions. While all PMAAs were pH sensitive and showed an increase in hydrodynamic radius ( ) with pH in the dilute regime, the of star polymers (measured at basic pH values) was significantly smaller for the star polyacids due to their more compact structure.
View Article and Find Full Text PDFWant 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!