相关论文: Fractal Magneto-conductance Fluctuations in Mesosc…
Whereas much work in the mathematical literature on quantum chaos has focused on phenomena such as quantum ergodicity and scarring, relatively little is known at the rigorous level about the existence of eigenfunctions whose morphology is…
Radio broadband spectro-polarimetric observations are sensitive to the spatial fluctuations of the Faraday depth (FD) within the telescope beam. Such FD fluctuations are referred to as "Faraday complexity", and can unveil small-scale…
The spectral fluctuation properties of various two- and three-dimensional superconducting billiard systems are investigated by employing the correlation-hole method. It rests on the sensitivity of the spectral Fourier transform to long…
Superconducting fluctuations (SF) in SmFeAsO$_{0.8}$F$_{0.2}$ (characterized by superconducting transition temperature $T_{c} \simeq 52.3$ K) are investigated by means of isothermal high-resolution dc magnetization measurements. The…
Based on very accurate measurements performed on a superconducting microwave resonator shaped like a desymmetrized three-dimensional (3D) Sinai billiard, we investigate for the first time spectral properties of the vectorial Helmholtz, i.e.…
We consider the semiclassical quantization of the Sinai billiard for disk radii R small compared to the wave length 2 pi/k. Via the application of the periodic orbit theory of diffraction we derive the semiclassical spectral determinant.…
A statistical analysis of the eigenfrequencies of two sets of superconducting microwave billiards, one with mushroom-like shape and the other from the familiy of the Limacon billiards, is presented. These billiards have mixed…
In this work, we study a family of fully chaotic billiards that exhibits only rotational symmetries, whose geometry is based on the $C_3$ symmetry system proposed by Leyvraz, Schmit, and Seligman~(LSS) in 1996. Quantum spectral analyses are…
We compute the decay of the autocorrelation function of the observable $|v_x|$ in the Sinai billiard and of the observable $v_x$ in the associated Lorentz gas with an approximation due to Baladi, Eckmann and Ruelle. We consider the standard…
Using reciprocity, we investigate the breaking of time-reversal (T) symmetry due to a ferrite embedded in a flat microwave billiard. Transmission spectra of isolated single resonances are not sensitive to T-violation whereas those of pairs…
We consider chaotic billiards in d dimensions, and study the matrix elements M_{nm} corresponding to general deformations of the boundary. We analyze the dependence of |M_{nm}|^2 on \omega = (E_n-E_m)/\hbar using semiclassical…
We study the isolated resonances occurring in conductance fluctuations of ballistic electron systems with a classically mixed phase space. In particular, we calculate the conductance and Wigner-Smith time as well as scattering states and…
We present experimental studies of the geometry-specific quantum scattering in microwave billiards of a given shape. We perform full quantum mechanical scattering calculations and find an excellent agreement with the experimental results.…
We introduce a boundary integral method for two-dimensional quantum billiards subjected to a constant magnetic field. It allows to calculate spectra and wave functions, in particular at strong fields and semiclassical values of the magnetic…
A quantum theory of the spin-dependent scattering of semiconductor electrons by a Schottky barrier at an interface with a ferromagnet is presented. The reflection of unpolarized non-equilibrium carriers produces spontaneous…
We report the theoretical prediction of a new class of spintronic materials, namely bipolar magnetic semiconductor (BMS), which is also supported by our experimental data. BMS acquires a unique band structure with unequal band gaps for spin…
The elastic mean free path of carriers in a recently introduced model of quantum chaotic billiards in two and three dimensions is calculated. The model incorporates surface roughness at a microscopic scale by randomly choosing the atomic…
We present a comprehensive semiclassical investigation of the three-dimensional Sinai billiard, addressing a few outstanding problems in "quantum chaos". We were mainly concerned with the accuracy of the semiclassical trace formula in two…
We report on the experimental realization of a flat, superconducting microwave resonator, a microwave billiard, with partially violated time-reversal (T ) invariance, induced by inserting a ferrite into the cavity and magnetizing it with an…
The non-collinear spin configurations cause many nontrivial phenomena related to the Berry phase. They are described by the vector spin chirality $\chi_{ij} ={\bf S}_i\times{\bf S}_j$ or scalar spin chirality $\chi_{ijk}=({\bf S}_i \times…