A spin valve is a microelectronic device in which high- and low-resistance states are realized by using both the charge and spin of carriers. Spin-valve structures used in modern hard-drive read heads and magnetic random access memoriescomprise two ferromagnetic electrodes whose relative magnetization orientations can be switched between parallel and antiparallel configurations, yielding the desired giant or tunnelling magnetoresistance effect. Here we demonstrate more than 100% spin-valve-like signal in a NiFe/IrMn/MgO/Pt stack with an antiferromagnet on one side and a non-magnetic metal on the other side of the tunnel barrier. Ferromagneticmoments in NiFe are reversed by external fields of approximately 50  mT or less, and the exchange-spring effect of NiFe on IrMn induces rotation of antiferromagnetic moments in IrMn, which is detected by the measured tunnelling anisotropic magnetoresistance. Our work demonstrates a spintronic element whose transport characteristics are governed by an antiferromagnet. It demonstrates that sensitivity to low magnetic fields can be combined with large, spin-orbit-coupling-induced magnetotransport anisotropy using a single magnetic electrode. The antiferromagnetic tunnelling anisotropic magnetoresistance provides a means to study magnetic characteristics of antiferromagnetic films by an electronic-transport measurement.

Axons are traditionally considered stable transmission cables, but evidence of the regulation of action potential propagation demonstrates that axons may have more important roles. However, their small diameters render intracellular recordings challenging, and low-magnitude extracellular signals are difficult to detect and assign. Better experimental access to axonal function would help to advance this field. Here we report methods to electrically visualize action potential propagation and network topology in cortical neurons grown over custom arrays, which contain 11,011 microelectrodes and are fabricated using complementary metal oxide semiconductor technology. Any neuron lying on the array can be recorded at high spatio-temporal resolution, and simultaneously precisely stimulated with little artifact. We find substantial velocity differences occurring locally within single axons, suggesting that the temporal control of a neuron's output may contribute to neuronal information processing.

Cyclodextrin based supramolecular polymers have been prepared using a β-cyclodextrin dimer and ditopic guest dimers having adamantyl groups. The ditopic guest dimers with various flexibility and adamantyl moieties were prepared to investigate the conformation of supramolecular polymers. The ditopic adamantane guest dimer C0 has a stiff spacer having a 4,4‘-bipyridinium group between adamantyl groups. The ditopic adamantane guest dimers, C2 and C3, have flexible methylene spacers. The ROESY spectra of the β-cyclodextrin dimer with the ditopic adamantane guest dimers showed NOE between the protons of adamantyl substituents and the inner protons of cyclodextrin. The ditopic adamantane guest dimers, C2 and C3 formed cyclic supramolecular oligomers in aqueous solutions. The cyclic structure was observed by atomic force microscopy (AFM). On the contrary, the ditopic adamantane guest dimer C0 formed the high molecular weight supramolecular polymers.