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Controllable manipulation of specific spin configurations of magnetic materials is the key to constructing functional spintronic devices. Here, it is demonstrated by integrating the merits of ferromagnetic, ferrimagnetic, and antiferromagnetic spin configurations into one synthetic antiferromagnetic (SAF) heterostructure by controlling both long-range oscillatory interlayer coupling and neighboring ferrimagnetic coupling. A controllable manipulation of four types of spin configurations of the Pt/[Co/Pt/Co]/Ru/CoTb SAF heterostructures composed of ferromagnetic Co/Pt/Co and ferrimagnetic CoTb layers is successfully achieved. In particular, the compensated magnetization, enhanced anomalous Hall resistance in the remanence state, wide-temperature spin-orbit torque switching of magnetization, and high immunity to the external magnetic field are simultaneously obtained in one of the SAF heterojunctions with macroscopic interlayer antiferromagnetic coupling. This design concept of engineering spin configurations may enable efficient spin manipulation for customized memory and logic applications.

This work was supported by the National Science Foundation of China (Grant Nos. 11434006, 11774199, and 51871112), the National Basic Research Program of China (Grant No. 2015CB921502), the 111 ProjectB13029, and the Taishan Scholar Program of Shandong Province. H.Z. was supported by the King Abdullah University of Science and Technology (KAUST) during his visit to KAUST. X.X.Z. acknowledges the support from KAUST.

We report the magneto-photoluminescence spectroscopy measurements on single CdSe/ZnSe self-assembled QDs. The evolution of the single dot excitonic transition lines exhibits an abnormal energy shift which deviates from the diamagnetic shift and linewidth broadening under magnetic field, followed by the photoluminescence quench at a certain magnetic field. A model involving electron cyclotron motion and tunneling processes is proposed to interpret these novel phenomena and is verified by the coincidence of the large energy shift and the linewidth broadening. This mechanism could be an effective way of external control of charges and optical properties of single QDs. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Nanocrystalline anatase TiO2 films were prepared from colloidal suspensions using particles with a nominal size of 12 nm. Their structure was examined by Raman spectroscopy and X-ray diffraction (XRD). The as-prepared specimens exhibit exclusively features due to the anatase phase of TiO2 (e.g., the Eg, B1g and A1g vibration modes in Raman spectroscopy and the characteristic diffraction peaks in XRD). Isochronal annealing of the films in air at temperatures of up to 1320 K effected clear structural changes, observed both in Raman and XRD: the crystallite size increases from ∼13 nm to ∼125 nm between 470 K and 1220 K, with the crystallites remaining in the anatase phase. A phase transition to the rutile phase of TiO2 occurs gradually in the temperature range 1220 – 1320 K and the average crystallite size increases to ∼160 nm. The Eg vibration in anatase films reveals a blue shift and an asymmetric peak broadening towards higher frequencies for smaller particle size/lower annealing temperatures. A power-law dependence between the Raman peak width and the inverse of the crystallite size is found. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The objective of the minimum toll revenue (MINREV) problem is to find tolls that simultaneously cause users to use the transportation network efficiently and minimize the total toll revenues that must be collected. This article investigates the Dantzig-Wolfe (DW) decomposition as an approach for solving the MINREV problem and establishes its relationships with a cutting plane algorithm and other proposed approaches. The article also identifies the variant of DW decomposition most suitable for implementation. Numerical experiments with real transportation networks suggest that DW decomposition is robust and should be used when the problems are too large for standard linear programming software. Although transportation planning is the application emphasized in this article, it should be noted that the MINREV problem also has applications in telecommunication network design and control. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 142–150 2004