Attenuation characteristics of spin pumping signal due to travelling spin waves

The authors have investigated the contribution of the surface spin waves to spin pumping. A Pt/NiFe bilayer has been used for measuring spin waves and spin pumping signals simultaneously. The theoretical framework of spin pumping resulting from ferromagnetic resonance has been extended to incorporate spin pumping due to spin waves. Equations for the effective area of spin pumping due to spin waves have been derived. The amplitude of the spin pumping signal resulting from travelling waves is shown to decrease more rapidly with precession frequency than that resulting from standing waves and show good agreement with the experimental data

Spin waves interference from rising and falling edges of electrical pulses

The authors have investigated the effect of the electrical pulse width of input excitations on the generated spin waves in a NiFe strip using pulse inductive time domain measurements. The authors have shown that the spin waves resulting from the rising- and the falling-edges of input excitation pulses interfere either constructively or destructively, and have provided conditions for obtaining spin wave packets with maximum intensity at different bias conditions

Detection of domain wall eigenfrequency in infinity-shaped magnetic nanostructures

The dynamics of a magnetic infinity-shaped nanostructure has been experimentally studied by two different techniques such as the sinusoidal resonance excitation and the damped short pulse excitation to measure the eigenfrequency of domain walls. Direct observation of the magnetic domain wall nucleation has been measured in the frequency domain. Electrical measurements of the domain wall dynamics in the frequency domain reveal the existence of multi-eigenmodes for large excitation amplitudes. The time-resolved measurements show that the frequency of the damped gyration is similar to that of the frequency domain and coexistence of spin wave excitations.Comment: arXiv admin note: substantial text overlap with arXiv:1110.011

Develmental patterns of Korean EFL learners' English argument structure constructions

The present study aims to explore developmental patterns of constructional knowledge of Korean EFL learners. The study asked120 Korean learners of English to carry out a sentence sorting and a translation task, and investigated how the participants atthree different proficiency levels use their constructional knowledge to comprehend English sentences. The results from thesorting task showed that the learners in the beginner group relied more heavily on verb-centered sorting than the learners in theintermediate group. The results from the translation task revealed that the L2 learners ability to comprehend complexconstructions is highly correlated with their proficiency in the target language. The study suggests that L2 learners' constructionalknowledge is acquired incrementally as their exposure to the target language extends, supporting one of the main premises of theusage-based approach to language and language acquisition.OAIID:oai:osos.snu.ac.kr:snu2013-01/102/0000001658/1SEQ:1PERF_CD:SNU2013-01EVAL_ITEM_CD:102USER_ID:0000001658ADJUST_YN:NEMP_ID:A002679DEPT_CD:707CITE_RATE:0FILENAME:developmental patterns of korean efl learners english argument structure constructions.docDEPT_NM:영어교육과EMAIL:[email protected]:

Ambipolar bistable switching effect of graphene

Reproducible current hysteresis is observed in graphene with a back gate structure in a two-terminal configuration. By applying a back gate bias to tune the Fermi level, an opposite sequence of switching with the different charge carriers, holes and electrons, is found. The charging and discharging effect is proposed to explain this ambipolar bistable hysteretic switching. To confirm this hypothesis, one-level transport model simulations including charging effect are performed and the results are consistent with our experimental data. Methods of improving the ON/OFF ratio of graphene resistive switching are suggested