Multiferroic nanodots can be harnessed to aid the development of the next generation of nonvolatile data storage and multi-functional devices. In this paper, we review the computational aspects of multiferroic nanodot materials and designs that hold promise for the future memory technology. Conception, methodology, and systematical studies are discussed, followed by some up-to-date experimental progress towards the ultimate limits. At the end of this paper, we outline some challenges remaining in multiferroic research, and how the first principles based approach can be employed as an important tool providing critical information to understand the emergent phenomena in multiferroics.
Multiferroic materials are currently the subject of intensive research worldwide, because of both their fundamental scientific problems and also possible technological applications. Among a number of candidates in the laboratories, compounds consisting of rare earth and transition metal perovskite oxides have very unusual structural and physical properties. In contrast to the so-called type I multiferroics, ferroelectricity may be induced by magnetic ordering or by applying external fields. In this review, the recent progress on the experimental and theoretical studies of some selected type II multiferroics is presented, with a focus on the perovskite oxides containing rare earth and transition metal elements. The rare earth orthoferrite crystals, rare earth titanate strained film, and rare earthbased superlattices are systematically reviewed to provide a broad overview on their promising electric, magnetic, and structural properties. The recent experimental advances in single-crystal growth by optical floating zone method are also presented. First-principles investigations, either supported by experimental results or awaiting for experimental verifications, are shown to offer useful guidance for the future applications of unconventional multiferroics.
All atomistic molecular dynamics simulations were performed on poly(amidoamine)(PAMAM) dendrimers that compound non-covalently with anticancer drug molecules including DOX,MTX,CE6,and SN38.The binding energies as well as their associated interaction energies and deformation energies were combined to evaluate the relative binding strength among drug,PAMAM,and PEG chains.We find that the deformation of dendrimers due to drug loading plays a crucial role in the drug binding.It is energetically favorable for the drug molecules to bind with PAMAM while the drugs bind with PEG metastable chains via kinetic confinement.Surface PEGylation helps dendrimers to accommodate more drug molecules with greater strength without inducing too much expansion.This work indicates that tuning the functionalized terminal groups of dendrimers is critical to design efficient dendrimer-based drug delivery systems.
