Here, we outline magnetoelectric (ME) device concepts based on the voltage control of the interface magnetism of an ME antiferromagnet gate dielectric formed on a very thin semiconductor channel with large spin-orbit coupling (SOC). The emphasis of the ME spin field-effect transistors (ME spin FET) is on an antiferromagnet spin-orbit read logic device and a ME spin-FET multiplexer. Both spin-FET schemes exploit the strong SOC in the semiconducting channel materials but remain dependent on the voltage-induced switching of an ME, so that the switching time is limited only by the switching dynamics of the ME. The induced exchange field spin polarizes the channel material, breaks time-reversal symmetry, and results in the preferential charge transport direction, due to the spin-orbit-driven spin-momentum locking. These devices could provide reliable room temperature operation with large on/off ratios, well beyond what can be achieved using magnetic tunnel junctions. All of the proposed device spintronic functionalities without the need to switch a ferromagnet, yielding a faster writing speed (∼10 ps) at a lower cost in energy (∼10 aJ), excellent temperature stability (operational up to 400 K or above), and requiring far fewer device elements (transistor equivalents) than CMOS.INDEX TERMS Magnetoelectric (ME) transistor, nonvolatile logic and memory, spin-orbit coupling (SOC).

With the rapid iteration of portable electronics and electric vehicles, developing high-capacity batteries with ultra-fast charging capability has become a holy grail. Here we report rechargeable aluminum-ion batteries capable of reaching a high specific capacity of 200 mAh g−1. When liquid metal is further used to lower the energy barrier from the anode, fastest charging rate of 104 C (duration of 0.35 s to reach a full capacity) and 500% more specific capacity under high-rate conditions are achieved. Phase boundaries from the active anode are believed to encourage a high-flux charge transfer through the electric double layers. As a result, cationic layers inside the electric double layers responded with a swift change in molecular conformation, but anionic layers adopted a polymer-like configuration to facilitate the change in composition.

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The four dopants (Nd, Gd, Dy, and Er) substitutionally occupy the Li + sites in lithium tetraborate (Li 2 B 4 O 7 : RE) glasses as determined by analysis of the extended X-ray absorption fine structure. The dopants are coordinated by 6-8 oxygen at a distance of 2.3 to 2.5 Å, depending on the rare earth. The inverse relationship between the RE-O coordination distance and rare earth (RE) atomic number is consistent with the expected lanthanide atomic radial contraction with increased atomic number. Through analysis of the X-ray absorption near edge structure, the rare earth dopants adopt the RE 3+ valence state. There are indications of strong rare earth 5d hybridization with the trigonal and tetrahedral formations of BO 3 and BO 4 based on the determination of the rare earth substitutional Li + site occupancy from the X-ray absorption near edge structure data. The local oxygen disorder around the RE 3+ luminescence centers evident in the structural determination of the various glasses, and the hybridization of the RE 3+ dopants with the host may contribute to the asymmetry evident in the luminescence emission spectral lines. The luminescence emission spectra are indeed characteristic of the expected f-to-f transitions; however, there is an observed asymmetry in some emission lines.