Non-Fermi liquid states in the pressurized CeCu2(Si1−xGex)2CeCu_2(Si_{1-x}Ge_x)_2 system: two critical points

In the archetypal strongly correlated electron superconductor CeCu$_2$Si$_2$ and its Ge-substituted alloys CeCu$_2$(Si$_{1-x}$Ge$_{x}$)$_2$ two quantum phase transitions -- one magnetic and one of so far unknown origin -- can be crossed as a function of pressure \cite{Yuan 2003a}. We examine the associated anomalous normal state by detailed measurements of the low temperature resistivity ($\rho$) power law exponent $\alpha$. At the lower critical point (at $p_{c1}$, $1\leq\alpha\leq 1.5$) $\alpha$ depends strongly on Ge concentration $x$ and thereby on disorder level, consistent with a Hlubina-Rice-Rosch scenario of critical scattering off antiferromagnetic fluctuations. By contrast, $\alpha$ is independent of $x$ at the upper quantum phase transition (at $p_{c2}$, $\alpha\simeq 1$), suggesting critical scattering from local or Q=0 modes, in agreement with a density/valence fluctuation approach.Comment: 4 pages, including 4 figures. New results added. Significant changes on the text and Fig.

Can board climate-responsible orientation improve corporate carbon performance? The moderating role of board carbon awareness and firm reputation

Overwhelming evidence from prior research suggests the functions of the board of directors have a vital influence on carbon performance. However, very little is known about the moderating effect of board functions. This study attempts to fill this gap by developing and empirically testing a conceptual model that highlights the role of board carbon awareness and firm reputation in the relationship between board climate-responsible orientation (BCO) and carbon performance. Using a fixed effect model to analyze data from 665 US listed firms covering a period of 2010–2019, we find that BCO and carbon performance show a U-shaped non-linear relationship. Increased experience of BCO improves corporate carbon performance. The results also provide evidence of the moderating effect of carbon awareness and firm reputation on the relationship between BCO and carbon performance. Carbon awareness reduces symbolic emission reduction actions in carbon management, while, firm reputation will cause symbolic emission reduction actions. Besides, splitting the sample according to firm size and carbon dependency shows BCO has a better effect on the carbon performance of small or medium-sized and high carbon-dependency firms. The findings have important implications for managers to use firm governance mechanisms to improve carbon performance

Science mapping approach to assisting the review of construction and demolition waste management research published between 2009 and 2018

Sustainable treatments of construction and demolition (C&D) wastes have become an increasingly urgent social, environmental, and economic issue worldwide. Based on a filter of 370 articles related to C&D waste management, this review-based study adopted a science mapping approach to evaluating the recent decade’s C&D waste management research. Through a three-step workflow consisting of bibliometric literature search, scientometric analysis, and qualitative discussion, this study identified the most influential journals, scholars, articles, and countries that have been active and influential in the C&D waste management research since 2009. Keyword analysis revealed the emerging research topics, such as BIM, prefabricated construction, Big Data, and Circular Economy. The follow-up discussion summarized the mainstream research areas (e.g., qualification of waste generation), discussed research gaps (e.g., integration of BIM and Big Data into C&D waste management), and proposed the framework for near-future research, such as a comprehensive evaluation of the performance of C&D waste diversion, human factors, and design and planning for waste diversion. By providing the big picture of the latest research in C&D waste management since 2009, the paper serves as a multi-disciplinary guide for practitioners and researchers to link current research areas into future trends

Next-to-Leading Order Corrections to Single Top Quark Production and Decay at the Tevatron: 1. s-channel Process

We present a study of s-channel single top quark production at the upgraded Tevatron $p\bar{p}$ collider, including the next-to-leading order (NLO) QCD corrections to the production and the decay of the top quark. The "modified" narrow width approximation was adopted to preserve the spin of the top quark in its production and decay. We discuss the effect of the different $O(\alpha_s)$ contributions on the inclusive cross section as well as various kinematic distributions after imposing the relevant cuts to select s-channel single top signal events. In particular the $O(\alpha_s)$ decay contribution, while small in size, has a significant impact on several distributions. With the help of the best-jet algorithm to reconstruct the top quark we demonstrate that it is possible to study kinematical and spin correlations in s-channel single top events. We furthermore compare top quark spin measurements in two different basis and show how NLO corrections have to be taken into consideration in searches for the Higgs boson through $W^{\pm}H$ associated production at the Tevatron.Comment: 39 pages, 37 figure

A Penetration Depth Study on Li2Pd3B and Li2Pt3B

In this paper we present a penetration depth study on the newly discovered superconductors Li$_2$Pd$_3$B and Li$_2$Pt$_3$B. Surprisingly, the low-temperature penetration depth $f(T)$ demonstrates distinct behavior in these two isostructural compounds. In Li$_2$Pd$_3$B, $f(T)$ follows an exponential decay and can be nicely fitted by a two-gap BCS superconducting model with a small gap $\delta_1=3.2$K and a large gap $\delta_2=11.5$K. However, linear temperature dependence of $f(T)$ is observed in Li$_2$Pt$_3$B below 0.3$T_c$, giving evidence of line nodes in the energy gap.Comment: 2 pages, submitted to LT2