Fermionic systems

Xem 1-4 trên 4 kết quả Fermionic systems
  • In this chapter we discuss relations between information theory and statistical mechanics. We show that the canonical and grand canonical distributions can be obtained from Shannon’s principle of maximum uncertainty [1, 2, 3]. Moreover, the time evolution of the entropy of an isolated system and the H theorem are discussed.

    pdf153p beobobeo 01-08-2012 35 8   Download

  • We study the magnetic ordered phases of the spin-1/2 Heisenberg antiferromagnetic model with nearest J1 and next nearest neighbor J2 exchange interactions on the square lattice using fermionic representation of spin operators within Popov-Fedotov approach.The unphysical states are eliminated on each site by introducing an imaginary chemical potential. Working in local coordinate system for every site we investigate the different ordered phases in dependence on exchange parameters. At T = 0 we recover the conventional spin wave results.

    pdf8p thuyliebe 09-10-2018 2 0   Download

  • We study the N´eel state of the spin 1 2 Heisenberg antiferromagnet model on hypercubic and triangular lattices, employing an auxiliary fermion representation for spin operators with Popov-Fedotov trick. The unphysical states are eliminated on each site by introducing an imaginary chemical potential. Working in local coordinate systems we obtain the free energy and the sublattice magnetization for both lattices in an unified manner. We show that exact treatment of the single occupancy constraint gives a significant effect at finite temperatures.

    pdf11p nguyenthuy1207 13-10-2018 0 0   Download

  • Carbon nanotubes are rolled up graphene sheets with a quasi-one-dimensional structure of nanometer-scale diameters. More than twenty years have passed since the pioneering work on carbon nanotubes by Prof. Iijima in 1991. During all these years, carbon nanotubes have at‐ tracted a lot of attention from physicists, chemists, material scientists, and electronic device engineers because of their excellent structural, electronic, optical, chemical, and mechanical properties.

    pdf0p lyly_5 22-03-2013 29 5   Download

CHỦ ĐỀ BẠN MUỐN TÌM

Đồng bộ tài khoản