Refine
Has Fulltext
- no (3)
Document Type
- Article (3)
Language
- English (3)
Is part of the Bibliography
- yes (3)
Institute
Previous research on young children's knowledge of prosodic focus marking has revealed an apparent paradox, with comprehension appearing to lag behind production. Comprehension of prosodic focus is difficult to study experimentally due to its subtle and ambiguous contribution to pragmatic meaning. We designed a novel comprehension task, which revealed that three- to six-year-old children show adult-like comprehension of the prosodic marking of subject and object focus. Our findings thus support the view that production does not precede comprehension in the acquisition of focus. We tested participants speaking English, German, and French. All three languages allow prosodic subject and object focus marking, but use additional syntactic marking to varying degrees (English: dispreferred; German: possible; French preferred). French participants produced fewer subject marked responses than English participants. We found no other cross-linguistic differences. Participants interpreted prosodic focus marking similarly and in an adult-like fashion in all three languages.
Using magneto-optical Faraday and Kerr measurements, we investigate the magnetic and magnetooptical properties of a thick Bi-substituted gadolinium iron garnet film over a broad range of wavelengths (250-850 nm) and temperatures (150-300 K), including the magnetization compensation point, TM. We observe an exchange-bias-like effect in the vicinity of TM. By slightly changing the sample temperature, we can precisely tune the bias field, which reaches a magnitude 6 times higher than the coercive field. We explain this phenomenon by considering the short-range superexchange interaction and a change in the magnetic behavior when moving from the surface to the bulk of the film. This finding may lead to the development of single-film magneto-optical devices based on the exchange-bias effect.
Understanding the damping is an important fundamental problem with widespread implications in magnetic technology. Ferrimagnetic materials offer a rich platform to explore not only the damping of the ferromagnetic mode, but also the damping of the high-frequency exchange mode very promising for ultrafast devices. Here we use time-resolved magneto-optical Kerr effect to investigate the ferromagnetic and exchange resonance modes and their damping in the bismuth-doped gadolinium iron garnet over a broad range of magnetic fields (0-10 T) and temperatures (50-300 K) including the magnetization and angular compensation points. These two resonance modes are excited via the inverse Faraday effect and unambiguously identified by their distinct frequency dependence on temperature and magnetic field. The temperature-dependent measurements in the external magnetic field H-ext = 2 T revealed that the intrinsic damping of the ferromagnetic mode is always smaller than the one of the exchange modes and both have a maximum near the angular compensation point. These results are fully consistent with recent predictions of atomistic simulations and a theory based on two-sublattice Landau-Lifshitz-Bloch equation. We also demonstrate that the damping of these modes varies differently as a function of H-ext. We explain the observed behaviors by considering the different features of the effective fields defining the precession frequencies of the ferromagnetic and exchange modes.