Determination of resonance Raman scattering cross sections of laser dyes using a traveling-wave amplifier

Received: 1 April 1998/Revised version: 20 April 1998     

Mid-infrared spectroscopic detection of trace gases using guided-wave difference-frequency generation

Received: 1 April 1998/Revised version: 29 April 1998     

Low-energy Raman-active phonons of multiwalled carbon nanotubes

Received: 8 April 1998/Accepted: 9 April 1998     

Focusing dependence of the efficiency of a singly resonant optical parametric oscillator

Received: 15 February 1998/Revised version: 6 April 1998     

Strain-driven self-organization of nanostructures on semiconductor surfaces

Received: 14 April 1998/Accepted: 23 October 1998     

Adiabatical stability of density distributions under Vlasov dynamics

It is shown using Vlasov dynamics that the density distribution corresponding to a mean field Bose condensate in an external time dependent potential is adiabatically stable whereas density distributions corresponding to finite temperature are not. Received: 27 February 1998 / Revised: 20 April 1998 / Accepted: 23 April 1998     

The mechanism of nanostructuring upon nanosecond laser irradiation of a STM tip

Received: 20 April 1998/Accepted: 2 June 1998     

Modeling and computer simulation of pulsed-laser-induced ablation

Received: 21 April 1998 / Accepted: 21 September 1998 / Published online: 24 February 1999     

Electronic structure and quantum transport in carbon nanotubes

Received: 3 April 1998     

High-repetition-rate eyesafe intracavity optical parametric oscillator

Received: 15 December 1997/Revised version: 27 April 1998     

Imaging within highly scattering media using time-resolved backscattering of femtosecond pulses

Received: 17 April 1998     

Novel massive ground states of spin chains in a magnetic field

Novel massive quantum states appearing in spin chains under a strong magnetic field are discussed. These states lead to plateaus in magnetization curves. When the systems are axially symmetric and the field is applied parallel to the symmetry-axis, the phenomena are analogous to metal-insulator transitions. Striking features of the plateau phenomena - exactness and rationality - are explained as consequences the commensurability condition to the underlying lattice. The effects of the planar anisotropy are also discussed in detail. Received: 16 February 1998 / Revised: 20 April 1998 / Accepted: 30 April 1998     

Zinc oxide thin films prepared by means of Langmuir–Blodgett multilayers

Recieved: 7 April 1998/Accepted: 31 July 1998     

X-ray emission in the ‘water window’ from a nitrogen gas puff target irradiated with a nanosecond Nd:glass laser pulse

Received: 20 April 1998/Revised version: 19 June 1998     

Quantum-Monte-Carlo simulations of polyethylene

The diffusion Quantum-Monte-Carlo method of solving the Schr?dinger equation is applied to the vibrational ground state of a polyethylene molecule. The results for the ground state energy show good agreement with normal mode analysis. In addition to stretching, bending and torsional interaction van-der-Waals interaction is applied to a single chain showing a decrease of the energy of 5%. The decrease for a polyethylene system of 5 chains with 10 atoms per molecule at the positions of a unit cell is determined to be 4.8% per molecule. Finally first steps towards simulating excited states were performed. Received: 9 February 1998 / Revised: 2 April 1998 / Accepted: 23 April 1998     

On the Fermi surface of some organic superconductors with sizeable critical temperatures

Recent studies of the Fermi surface of quasi-two-dimensional organic conductors comfort the idea that the presence of a van Hove anomaly near the Fermi level is a favourable factor for superconductivity. Received: 28 April 1998 / Revised and accepted: 13 May 1998     

Field theoretical calculation of the specific heat exponent for a classical N-vector model in a random external field

We calculate using diagrammatic perturbation theory in the two-loop approximation, the specific heat exponent for the classical N-vector model in a random external field for spatial dimension (D) lying between four and six. The calculation supports the modified hyperscaling , where is the correlation length exponent. Received: 18 March 1998 / Revised: 17 April 1998 / Accepted: 21 April 1998     

Fluctuation-dissipation ratio in lattice-gas models with kinetic constraints

We investigate by Monte-Carlo simulation the linear response function of three dimensional structural glass models defined by short-range kinetic constraints and a trivial equilibrium Boltzmann-Gibbs measure. The breakdown of the fluctuation-dissipation theorem in the glassy phase follows the prediction of mean field low temperature mode-coupling theory. Received: 24 April 1998 / Received in final form: 8 May 1998 / Accepted: 11 May 1998     

Low temperature thermodynamics of inverse square spin models in one dimension

We present a field-theoretic renormalization group calculation in two loop order for classical O(N)-models with an inverse square interaction in the vicinity of their lower critical dimensionality one. The magnetic susceptibility at low temperatures is shown to diverge like with a=(N-2)/(N-1) and . From a comparison with the exactly solvable Haldane-Shastry model we find that the same temperature dependence applies also to ferromagnetic quantum spin chains. Received: 20 February 1998 / Revised: 27 April 1998 / Accepted: 30 April 1998     

Resonance enhanced multiphoton ionization (REMPI) and REMPI-photoelectron spectroscopy of ammonia

Resonance enhanced multiphoton ionization (REMPI) spectroscopy, preferably linked with kinetic energy analysis of the resulting photoelectrons (REMPI-photoelectron spectroscopy (PES)), continues to make enormous contributions to our understanding of the spectroscopy and, in many cases, the decay dynamics of small molecules in excited (normally Rydberg) electronic states. Here we present results of recent REMPI and REMPI-PES studies involving the ammonia molecule which provide further illustration of some of the many opportunities offered by these techniques. Received: 28 January 1998 / Revised: 3 April 1998 / Accepted: 15 April 1998