Finite-size effects in metallic superlattice systems

Systematic study of finite-size effects in quantum Monte Carlo calculations of real metallic systems.

We present a systematic and comprehensive study of finite-size effects in diffusion quantum Monte Carlo calculations of metals. Several previously introduced schemes for correcting finite-size errors are compared for accuracy and efficiency, and practical improvements are introduced. In particular, we test a simple but efficient method of finite-size correction based on an accurate combination ...

Coulomb finite-size effects in quasi-two-dimensional systems

The model periodic Coulomb interaction (Williamson et al 1997 Phys. Rev. B 55 R4851) is a replacement for the Ewald sum, developed to reduce finitesize errors in the simulation of extended 3D systems. We investigate the generalization of this technique to quasi-2D systems; we show through testing in quantum Monte Carlo simulations that while the new interaction reduces the calculation time dram...

Boundary and finite-size effects in small magnetic systems

We study the effect of free boundaries in finite magnetic systems of cubic shape on the field and temperature dependence of the magnetisation within the isotropic model of D-component spin vectors in the limit D → ∞. This model is described by a closed system of equations and captures the Goldstone-mode effects such as global rotation of the magnetic moment and spin-wave fluctuations. We have o...

Finite Size Effects in Small Particle Systems`oscar

We present the results of Monte Carlo simulations of a model of a γ-Fe 2 O 3 (maghemite) single particle of spherical shape. The magnetic Fe 3+ ions are represented by Ising spins on a spinel lattice that consists on two sublattices with octhaedral and tetrahedral coordination with exchange interactions among them and with an external magnetic field. By varying the particle diameter, we have st...

Dynamics of Fluctuations in Driven Diffusive Systems: Finite-size Effects