Linearly polarized GHz magnetization dynamics of spin helix modes in the ferrimagnetic insulator Cu2_{2}OSeO3_{3}

Linear dichroism -- the polarization dependent absorption of electromagnetic waves -- is routinely exploited in applications as diverse as structure determination of DNA or polarization filters in optical technologies. Here filamentary absorbers with a large length-to-width ratio are a prerequisite. For magnetization dynamics in the few GHz frequency regime strictly linear dichroism was not observed for more than eight decades. Here, we show that the bulk chiral magnet Cu$_{2}$OSeO$_{3}$ exhibits linearly polarized magnetization dynamics at an unexpectedly small frequency of about 2 GHz. Unlike optical filters that are assembled from filamentary absorbers, the magnet provides linear polarization as a bulk material for an extremely wide range of length-to-width ratios. In addition, the polarization plane of a given mode can be switched by 90$^\circ$ via a tiny variation in width. Our findings shed a new light on magnetization dynamics in that ferrimagnetic ordering combined with anisotropic exchange interaction offers strictly linear polarization and cross-polarized modes for a broad spectrum of sample shapes. The discovery allows for novel design rules and optimization of microwave-to-magnon transduction in emerging microwave technologies.Comment: 20 pages, 4 figure

Low spin wave damping in the insulating chiral magnet Cu2_{2}OSeO3_{3}

Chiral magnets with topologically nontrivial spin order such as Skyrmions have generated enormous interest in both fundamental and applied sciences. We report broadband microwave spectroscopy performed on the insulating chiral ferrimagnet Cu$_{2}$OSeO$_{3}$. For the damping of magnetization dynamics we find a remarkably small Gilbert damping parameter of about $1\times10^{-4}$ at 5 K. This value is only a factor of 4 larger than the one reported for the best insulating ferrimagnet yttrium iron garnet. We detect a series of sharp resonances and attribute them to confined spin waves in the mm-sized samples. Considering the small damping, insulating chiral magnets turn out to be promising candidates when exploring non-collinear spin structures for high frequency applications.Comment: 5 pages, 5 figures, and supplementary materia

Competition and Gender Prejudice: Are Discriminatory Employers Doomed to Fail?

According to Becker's (1957) famous theory on discrimination, entrepreneurs with a strong prejudice against female workers forgo profits by submitting to their tastes. In a competitive market their firms lack efficiency and are therefore forced to leave. We present new empirical evidence for this prediction by studying the survival of startup firms in a large longitudinal matched employer-employee data set from Austria. Our results show that firms with strong preferences for discrimination, i.e. a low share of female employees relatively to the industry average, have significantly shorter survival rates. This is especially relevant for firms starting out with female shares in the lower tail of the distribution. They exit about 18 months earlier than firms with a median share of females. We see no differences in survival between firms at the top of the female share distribution and at the median, though. We further document that highly discriminatory firms that manage to survive submit to market powers and increase their female workforce over time

A meta-analysis of the investment-uncertainty relationship

In this article we use meta-analysis to investigate the investment-uncertainty relationship. We focus on the direction and statistical significance of empirical estimates. Specifically, we estimate an ordered probit model and transform the estimated coefficients into marginal effects to reflect the changes in the probability of finding a significantly negative estimate, an insignificant estimate, or a significantly positive estimate. Exploratory data analysis shows that there is little empirical evidence for a positive relationship. The regression results suggest that the source of uncertainty, the level of data aggregation, the underlying model specification, and differences between short- and long-run effects are important sources of variation in study outcomes. These findings are, by and large, robust to the introduction of a trend variable to capture publication trends in the literature. The probability of finding a significantly negative relationship is higher in more recently published studies. JEL Classification: D21, D80, E22 1

Gender Pay Gaps in the Former Soviet Union: A Review of the Evidence

The goal of this paper is to examine the patterns and movements of the gender pay gaps in the countries of the former Soviet Union (FSU) and to place them in the context of advanced economies. We survey over 30 publications and conduct a meta-analysis of this literature. Gender pay gaps in the region are considerable and above the levels observed in advanced economies. Similar to advanced economies, industrial and occupational segregation widens the gaps in the FSU countries, whereas gender differences in educational attainment tend to shrink them. However, a much higher proportion of the gaps remain unexplained, pointing toward the role of unobserved gender differences related to actual and perceived productivity. Over the last 25 years, the gaps contracted in most FSU countries, primarily due to the reduction in the unexplained portion. Underlying the contraction at the mean are different movements in the gap across the pay distribution. Although the glass-ceiling effect has diminished in some FSU countries, it has persisted in others. We investigate the reasons underlying these findings and argue that the developments in the FSU region shed new light on our understanding of the gender pay gaps

Gender gaps in education

This chapter reviews the growing body of research in economics which concentrates on the education gender gap and its evolution, over time and across countries. The survey first focuses on gender differentials in the historical period that roughly goes from 1850 to the 1940s and documents the deep determinants of the early phase of female education expansion, including preindustrial conditions, religion, and family and kinship patterns. Next, the survey describes the stylized facts of contemporaneous gender gaps in education, from the 1950s to the present day, accounting for several alternative measures of attainment and achievement and for geographic and temporal differentiations. The determinants of the gaps are then summarized, while keeping a strong emphasis on an historical perspective and disentangling factors related to the labor market, family formation, psychological elements, and societal cultural norms. A discussion follows of the implications of the education gender gap for multiple realms, from economic growth to family life, taking into account the potential for reverse causation. Special attention is devoted to the persistency of gender gaps in the STEM and economics fields