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We derive the effective Bose Hamiltonian for a system of interacting excitons applying the Usui transformation. The fermionic nonlinearities are consistently included, leading to a density dependent correction to the kinetic Hamiltonian and to a saturation ...
The stray field of permalloy (Py) micromagnets has been measured by means of a micrometer-sized Hall magnetometer incorporating a ballistic two-dimensional electron system. In particular, ferromagnetic specimens have been investigated where two micromagnet ...
Institute of Electrical and Electronics Engineers2002
We analyze the room temperature photoluminescence properties of several multilayer stackings of GaN/AlN quantum dots. We report drastic differences of emission energies and linewidths between continuous wave and time-resolved photoluminescence experiments. ...
We consider a random Schrödinger operator in an external magnetic field. The random potential consists of delta functions of random strengths situated on the sites of a regular two-dimensional lattice. We characterize the spectrum in the lowest N Landau ba ...
A family of cationic polyelectrolytes possessing defined chain lengths, narrow chain length distributions, uniform charge d., but substituents of different hydrophilicity at the quaternary ammonium group served as model compds. for adsorption studies. Thes ...
A Hamiltonian formulation of the relativistic guiding center drifts is extended to anisotropic pressure plasmas. The magnetic coordinates devised by Boozer are adapted to the anisotropic pressure model and retain canonical properties for two-dimensional an ...
We analyze the low temperature photoluminescence properties of two multi-layer stacking of GaN/AlN quantum dots. We report drastic differences of linewidths between continuous wave and time-resolved photoluminescence experiments. After the pulsed excitatio ...
We consider an electron in two dimensions submitted to a magnetic field and to the potential of impurities. We show that when the electron is confined to a half-space by a planar wall described by a smooth increasing potential, the total Hamiltonian necess ...
We show that triple-quantum-single-quantum (TQ-SQ) correlation spectra of crystalline and disordered solids can be obtained under MAS using pulse sequences based on through-bond J-couplings. The feasibility of the experiments in coupled spin-1/2 systems is ...
For chaotic systems there is a theory for the decay of the survival probability, and for the parametric dependence of the local density of states. This theory leads to the distinction between 'perturbative' and 'non-perturbative' regimes, and to the observ ...
