Search results for "Raj"
showing 10 items of 1155 documents
Spin torques and magnetic texture dynamics driven by the supercurrent in superconductor/ferromagnet structures
2018
We introduce the general formalism to describe spin torques induced by the supercurrents injected from the adjacent superconducting electrodes into the spin-textured ferromagnets. By considering the adiabatic limit for the equal-spin superconducting correlations in the ferromagnet we show that the supercurrent can generate both the field-like spin transfer torque and the spin-orbital torque. These dissipationless spin torques are expressed through the current-induced corrections to the effective field derived from the system energy. The general formalism is applied to show that the supercurrent can either shift or move the magnetic domain walls depending on their structure and the type of s…
Thermodynamics of a Phase-Driven Proximity Josephson Junction
2019
We study the thermodynamic properties of a superconductor/normal metal/superconductor Josephson junction {in the short limit}. Owing to the proximity effect, such a junction constitutes a thermodynamic system where {phase difference}, supercurrent, temperature and entropy are thermodynamical variables connected by equations of state. These allow conceiving quasi-static processes that we characterize in terms of heat and work exchanged. Finally, we combine such processes to construct a Josephson-based Otto and Stirling cycles. We study the related performance in both engine and refrigerator operating mode.
Anomalous current in diffusive ferromagnetic Josephson junctions
2017
We demonstrate that in diffusive superconductor/ferromagnet/superconductor (S/F/S) junctions a finite, anomalous Josephson current can flow even at zero phase difference between the S electrodes. The conditions for the observation of this effect are noncoplanar magnetization distribution and a broken magnetization inversion symmetry of the superconducting current. The latter symmetry is intrinsic for the widely used quasiclassical approximation and prevented previous works based on this approximation from obtaining the Josephson anomalous current. We show that this symmetry can be removed by introducing spin-dependent boundary conditions for the quasiclassical equations at the superconducti…
Jyväskylä
1837
Jyväskylä
1833
Jyväskylä
1851
Jyväskylä
Działalność Zagranicznego Komitetu Odbudowy Zamku Królewskiego w Warszawie (1967–1972)
2018
Zdecydowana większość emigracyjnych elit politycznych zajęła negatywne stanowisko w sprawie zbiórki pieniędzy na restytucję Zamku Królewskiego w Warszawie. W 1. połowie lat 70. XX w. na całym świecie działało jednak kilkadziesiąt komitetów i organizacji polonijnych wspierających ową inicjatywę, najwięcej w Stanach Zjednoczonych, Australii, we Francji i w Kanadzie. Chronologicznie pierwszy tego typu komitet zawiązał się jeszcze w czerwcu 1967 r. w Londynie, na kilka lat przed decyzją władz PRL w sprawie podniesienia z ruin byłej siedziby królewskiej. Przewodniczącym Zagranicznego Komitetu Odbudowy Zamku Królewskiego w Warszawie został Ignacy Czaykowski. W skład komitetu weszły osoby, które w…