Kronig-Penney-Ising picture of colossal magnetoresistance

Colossal magnetoresistance

We review recent experimental work falling under the broad classification of colossal magnetoresistance (CMR), which is magnetoresistance associated with a ferromagnetic-toparamagnetic phase transition. The prototypical CMR compound is derived from the parent compound, perovskite LaMnO3. When hole doped at a concentration of 20–40% holes/Mn ion, for instance by Ca or Sr substitution for La, the...

Colossal Magnetoresistance

Colossal magnetoresistance (CMR) effect was discovered among the manganese oxide class of materials, i.e. La1−xCaxMnO3. It shows large magnetoresistance by orders of magnitude, however several environmental requirements limit CMR toward general applications. Recently people have been focused on understanding a fundamental physics because of complex correlations between electron-lattice and elec...

Colossal Magnetoresistance

The classical diffusion - limited Kronig - Penney system

We have previously discussed the classical diffusive system of the bounded one-dimensional multitrap using the transfer-matrix method which is generally applied for studying the energy spectrum of the unbounded quantum Kronig-Penney multibarrier. It was shown, by this method, that for certain values of the relevant parameters the bounded multitrap array have unity transmission and a double-peak...

Quantum diffusion in the Kronig-Penney model

In this paper we consider the 1D Schrödinger operator H with periodic point interactions. We show an L1 − L∞ bound for the time evolution operator e−itH restricted to each energy band with decay order O(t−1/3) as t → ∞, which comes from some kind of resonant state. The order O(t−1/3) is optimal for our model. We also give an asymptotic bound for the coefficient in the high energy limit. For the...