Complex singularities in the specific heat of the SU(2) lattice gauge model

A recent Monte Carlo simulation showing a sharp peak versus β in the specific heat for an SU(2) lattice gauge theory is compared with the high temperature expansion. An interpretation based on complex β-plane singularities is proposed.     

Phase transitions of bipartite entanglement

We analyze the statistical properties of the entanglement of a large bipartite quantum system. By framing the problem in terms of random matrices and a fictitious temperature, we unveil the existence of two phase transitions, characterized by different spectra of the reduced density matrices.     

Diode-pumped single-frequency Tm:LiLuF(4) ring laser

We report a room-temperature single-frequency Tm:LiLuF(4) laser with a maximum output power of 120 mW, a slope efficiency of 13%, and a wavelength tunability range from 1875 to 1895 nm. Both frequency and relative intensity noise have been investigated, showing an emission linewidth of ~300 kHz over 1 ms observation time and an intensity noise spectrum limited by quantum noise for Fourier frequencies larger than 5 MHz.     

The Crossover Region Between Long-Range and Short-Range Interactions for the Critical Exponents

It is well know that systems with an interaction decaying as a power of the distance may have critical exponents that are different from those of short-range systems. The boundary between long-range and short-range is known, however the behavior in the crossover region is not well understood. In this paper we propose a general form for the crossover function and we compute it in a particular limit. We compare our predictions with the results of numerical simulations for two-dimensional long-range percolation.     

Calix[4]- and calix[5]arene-based multicavity macrocycles

Synthesis and single-crystal X-ray structures of mixed triple and double calixarenes 6 and 7, obtained from the base-catalyzed condensation of calix[5]arene 1 with cone pertosylated calix[4]arene 2, are reported. VT-NMR studies on 7 are consistent with a molecular motion arising from the anti-gauche conformational interconversion of its ethylene linkages.     

12-Acylindolo[1,2-c]quinazolines by palladium-catalyzed cyclocarbonylation of o-alkynyltrifluoroacetanilides

6-Trifluoromethyl-12-acylindolo[1,2-c]quinazolines are prepared in high yield through the palladium-catalyzed reaction of bis(o-trifluoroacetamidophenyl)acetylene with aryl or vinyl halides and triflates. The reaction, which tolerates a variety of important functional groups, probably involves the formation of a 3-acyl-2-(o-trifluoroacetamidophenyl)indole intermediate, followed by its cyclization to the indoloquinazoline product. [reaction: see text]     

On the distribution of the overlaps at given disorder

We prove a rigorous version of the following heuristic statement: if, in a spin glass model, the extended Ghirlanda–Guerra identities are valid, at given disorder the distribution of the overlap of two configurations is discrete, and its support (the smallest closed set that carries this distribution) is non-random. To cite this article: G. Parisi, M. Talagrand, C. R. Acad. Sci. Paris, Ser. I 339 (2004).