Two one-dimensional intercalating molybdenum oxide polymers have been synthesized using different structure-directing units under specific hydrothermal conditions. MoO-0 (NaNH4Mo3O10) was synthesized using tetramethylammonium hydroxide, and MoO-1(C6H18N2Mo4O13) was synthesized using 1,6-hexanediamine. The two crystal structures have been determined by the single-crystal X-ray diffraction method. Both consist of bundles of parallel molybdenum oxide chains interspersed with metals or organic cations which play the role of intercalating agent in the host structure. The Mo has a 6+ valence state and distorted octahedral coordination. Mo-0 has orthorhombic symmetry (Pnma, No. 62) with a = 8.407(2) Å, b = 7.603(2) Å, and c = 14.350(3) Å. MoO-1 has triclinic symmetry (P1̄, No. 2) with a = 8.267(2) Å, b = 8.986(2) Å, c = 12.714(3) Å, α = 87.58(3)°, β = 76.48(3)°, γ = 67.97(3)°. The study suggests that the structures and properties of intercalation-type molybdenum oxide polymers can be engineered by incorporating the structure-directing units, acidity, and the hydrothermal conditions.

Commercial electron‐beam resists are modified into semimetallic resists by doping with 1–3 nm metal nanoparticles, which improve the resolution, contrast, strength, dry‐etching resistance, and other properties of the resist. With the modified resists, fine resist nanopatterns from electron‐beam lithography are readily converted into 5–50 nm, high‐quality multilayers for metallic nanosensors or nanopatterns via ion‐beam etching. This method solves the problem of the fabrication of fine (<50 nm) metallic nanodevices via pattern transferring.

The continuing scaling of magnetic recording is facing more and more scientific and technological challenges because both the read sensor and recording bit are approaching sub-50 nm regime with the ever increasing areal density in hard disk drives. One of the key and indispensable elements for both high-sensitivity sensors and high-density media is the exchange bias between a ferromagnetic and an antiferromagnetic layer or the exchange coupling between two ferromagnets via a non-magnetic spacer. In the nanometer regime, the exchange coupling between ferromagnet and antiferromagnet or two ferromagnets through a conductive spacer is governed by the intergrain exchange interaction which has its origin in electron spins. Interlayer exchange coupling in multilayer or trilayer essentially originates from the quantum confinement effect. In this paper, we first review the physical origin and various theoretical models of the two types of exchange couplings, followed by a review of the applications of the exchange bias and interlayer exchange coupling in data storage with emphasis on the advanced read sensor and advanced media including perpendicular media and patterned media.

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