Table of contents

We construct and discuss the Fock-space representation for a deformed oscillator with "peculiar" statistics. We show that the corresponding algebra represents a deformed supersymmetric oscillator.

In the microwave "ionization" of excited 3d H atoms by a linearly polarized field, we observe experimentally for the first time a fine-scale frequency dependence that is suppressed when relatively weak broad-band noise is added to the driving field. We use 1d classical calculations, 1d quantal calculations and Husimi wave function distributions to give a semiclassical explanation for the delicate behavior.

We have re-evaluated the results of the neutron lifetime experiment based on storage of decay protons in a Penning trap. Combining improved statistical treatment of the data with precise measurements of the magnetic-field distribution in the trap, we arrive at a revised value τ_n = 889.2 ± 4.8 s.

A compressed monolayer of CH₃Cl adsorbed on graphite has been examined by X-ray diffraction, EXAFS and molecular-dynamics calculations (MD). A two-stage melting process with continuous melting in one spatial direction (T_m = 147 K), followed by a second process, which ultimately is discontinuous, has been found. The intermediate liquid state at 147 K < T < 156 K, recently suggested on the basis of a specific-heat measurement, has been identified as a liquid-crystal–like phase. It has a high degree of orientational order of the dipolar molecules.

The diffuse scattering located close to Bragg reflections has been studied as a function of the temperature on a single grain of the AlPdMn icosahedral phase. Between 600°C and 800°C there is a reversible and continuous transition. When the temperature increases, the diffuse scattering diminishes whereas high-Q_⊥ reflections have their intensity increased. All results are well interpreted within the elasticity theory of quasi-crystals: the changes in diffuse scattering shape and intensity when lowering the temperature are due to a softening of the K₁ phason elastic constant. The time decay of these long-wavelength phason fluctuations is larger than 5 ns.

Pure C₇₀ crystallizes in close-packed crystal structures. Both the hexagonal close packing (h.c.p.) and the cubic close packing (c.c.p.) are known to exist. X-ray diffraction from single crystals with hexagonal habitus shows rods of diffuse intensity typical of stacking faults. The intensities of three of these rods were measured at room temperature with synchrotron radiation, and interpreted with a growth fault model assuming a depth of interaction of three layers. The result indicates the presence of both h.c.p. and c.c.p. domains, the former containing fewer stacking faults than the latter. The probability to find an h-stack of three layers ( e.g., ABA) anywhere in the crystal is only about 60%.

We suggest that the slow, scale-invariant coarsening regime in faceting kinetics is governed by long-tailed algebraic distributions of kink-antikink reorganization times. This makes the problem similar to dispersive charge transport in disordered materials. A qualitative explanation is given for the low experimental value of the dynamic exponent (ϕ ≃ 1/6) describing the growth of groove width.

We report on a study of transport through metal-insulator-superconductor structures where the insulator is of the Anderson type. The I-V characteristics of such samples cross over from Andreev-dominated tunnelling to single-particle tunnelling as the normal-state resistance of the device exceeds 10 kΩ.

The electronic and vibrational free energies of the b.c.c., f.c.c. and h.c.p. phases of iron are calculated by ab initio band structure methods. The electronic and pV contributions to Gibbs energy show a non-linear dependence with temperature and play an important role for the h.c.p.-b.c.c. phase stability. The b.c.c. phase is found to be stable at low pressure. For large pressure, an upper limit of the magnetic entropy is estimated. It lowers Gibbs energy of the b.c.c. phase, but with all energy terms, h.c.p. included, remains stable at all temperatures.

We performed detailed theoretical and experimental studies on the neutralization of Na⁺-ions with keV energies in grazing scattering from a clean and flat Al(111) surface. Our data are described well by model calculations based on the non-perturbative CAM method. From the analysis of our experiments we deduce the effective binding energy of the NaI 3s-level in front of the metal surface.

Giant ferro-vesicles made with a lipidic bilayer and filled up with a chemically synthesized magnetic fluid present undulations of the membrane in zero field. A magnetic field externally applied flattens the thermal undulations, induces a shape deformation of the vesicle and makes it lengthen along the field direction. We analyse the field-dependent elongation of the ferro-vesicle and compare it to the theoretical model.

We consider the interaction between two rods embedded in a fluctuating surface which is governed by either surface tension or rigidity. The modification of fluctuations by the rods leads to an attractive long-range interaction that falls off as 1/R⁴ with their separation. The orientational dependence of the resulting interaction is non-trivial and may lead to interesting patterns of rod-like objects on such surfaces.

We comment on the work of L. G. Hanson, J. Zhang and P. Lambropoulos (Europhys. Lett.30 (2) pp. 81–86 (1995)). An error in their discussion of the long-time photoelectron spectrum is corrected.

The comment by Haan and Grobe (HG) consists of two parts: one represents an elaboration on essential states and related approximations in dealing with problems such as that in our paper. The second points out an error in one of our statements.