October 2012 Volume 11, Issue 10

Editorial

Inspiring interfaces   p827
doi:10.1038/nmat3440
The arts and social sciences communities could enhance the commercial prospects of new materials.

Research Highlights

Superlenses sharpen up | Interior design | Restrained fingering | Rare-earth ion singled out | Stepping up MoS₂ integration

News and Views

Letters

Quantum effect on thermally activated glide of dislocations   pp845 - 849
Laurent Proville, David Rodney and Mihai-Cosmin Marinica
doi:10.1038/nmat3401
The motion of dislocations under stress is a key process in crystal plasticity. The finding that at low temperatures differences between experiments and theoretical predictions of dislocation activation can be explained by quantum effects arising from crystal zero-point vibrations represents a significant advance in our understanding of plasticity.

See also: News and Views by Ackland

Spin excitations in a single La₂CuO₄ layer   pp850 - 854
M. P. M. Dean, R. S. Springell, C. Monney, K. J. Zhou, J. Pereiro, I. Božović, B. Dalla Piazza, H. M. Rønnow, E. Morenzoni, J. van den Brink, T. Schmitt and J. P. Hill
doi:10.1038/nmat3409
The dynamics of spins in single atomic layers of cuprates and other compounds are important for understanding their properties, such as magnetism and high-temperature superconductivity. Now, spin excitations in isolated single layers of a cuprate have been measured, providing valuable feedback on their magnetic properties.

Quantum many-body interactions in digital oxide superlattices   pp855 - 859
Eric J. Monkman, Carolina Adamo, Julia A. Mundy, Daniel E. Shai, John W. Harter, Dawei Shen, Bulat Burganov, David A. Muller, Darrell G. Schlom and Kyle M. Shen
doi:10.1038/nmat3405
The electronic interactions at the interface of oxide materials promise properties that can be very different from those of the parent compounds. The finding that many-body interactions in oxide superlattices can be used to engineer electronic properties offers a new strategy for designing oxide heterostructures.

See also: News and Views by Rondinelli & May

A ferroelectric memristor   pp860 - 864
André Chanthbouala, Vincent Garcia, Ryan O. Cherifi, Karim Bouzehouane, Stéphane Fusil, Xavier Moya, Stéphane Xavier, Hiroyuki Yamada, Cyrile Deranlot, Neil D. Mathur, Manuel Bibes, Agnès Barthélémy and Julie Grollier
doi:10.1038/nmat3415
Memristors are devices whose dynamic properties are of interest because they can mimic the operation of biological synapses. The demonstration that ferroelectric domains in tunnel junctions behave like memristors suggests new approaches for designing neuromorphic circuits.

Graphene field-effect transistors as room-temperature terahertz detectors   pp865 - 871
L. Vicarelli, M. S. Vitiello, D. Coquillat, A. Lombardo, A. C. Ferrari, W. Knap, M. Polini, V. Pellegrini and A. Tredicucci
doi:10.1038/nmat3417
Its high carrier mobility is one of the factors that makes graphene interesting for electronic and photonic applications at terahertz frequencies. Such possibilities are now further supported by the demonstration of an efficient room-temperature graphene detector for terahertz radiation that promises to be considerably faster than competing techniques.

Van der Waals interactions at metal/organic interfaces at the single-molecule level   pp872 - 876
Sriharsha V. Aradhya, Michael Frei, Mark S. Hybertsen and L. Venkataraman
doi:10.1038/nmat3403
Van der Waals interactions are critical to the understanding of functional metal/molecule interfaces in catalysis, molecular electronics and self-assembly. Such interactions have now been characterized at the single-molecule level through a combination of measurements of the stretching mechanics of molecular junctions and atomistic simulations.

See also: News and Views by van Ruitenbeek

Heterogeneous nucleation of organic crystals mediated by single-molecule templates   pp877 - 881
Koji Harano, Tatsuya Homma, Yoshiko Niimi, Masanori Koshino, Kazu Suenaga, Ludwik Leibler and Eiichi Nakamura
doi:10.1038/nmat3408
Mechanistic details on how a molecular crystal nucleates on a surface remain limited because it is difficult to probe rare events at the molecular scale. Now, single-molecule real-time transmission electron microscopy shows that a single-molecule template on the surface of carbon nanohorns can nucleate the crystallization of two organic compounds, and that the mechanism is reminiscent of a two-step nucleation process in solution.

See also: News and Views by Vekilov

Articles

Unification of trap-limited electron transport in semiconducting polymers   pp882 - 887
H. T. Nicolai, M. Kuik, G. A. H. Wetzelaer, B. de Boer, C. Campbell, C. Risko, J. L. Brédas and P. W. M. Blom
doi:10.1038/nmat3384
Electron transport in semiconducting polymers is usually inferior to hole transport, which is ascribed to charge trapping on defect sites. The observation of an identical electron-trap distribution in a range of materials now points to a common origin of these states that, as calculations suggest, may be related to hydrated oxygen complexes.

See also: News and Views by Köhler

Probing oxygen vacancy concentration and homogeneity in solid-oxide fuel-cell cathode materials on the subunit-cell level   pp888 - 894
Young-Min Kim, Jun He, Michael D. Biegalski, Hailemariam Ambaye, Valeria Lauter, Hans M. Christen, Sokrates T. Pantelides, Stephen J. Pennycook, Sergei V. Kalinin and Albina Y. Borisevich
doi:10.1038/nmat3393
Although oxygen vacancy distributions and dynamics control the operation of solid-oxide fuel cells, understanding the atomistic mechanisms involved during operation of the cell has proved difficult. An approach for the direct mapping of oxygen vacancy concentrations based on local lattice parameter measurements by scanning transmission electron microscopy is now proposed.

Combination delivery of TGF-ß inhibitor and IL-2 by nanoscale liposomal polymeric gels enhances tumour immunotherapy   pp895 - 905
Jason Park, Stephen H. Wrzesinski, Eric Stern, Michael Look, Jason Criscione, Ragy Ragheb, Steven M. Jay, Stacey L. Demento, Atu Agawu, Paula Licona Limon, Anthony F. Ferrandino, David Gonzalez, Ann Habermann, Richard A. Flavell and Tarek M. Fahmy
doi:10.1038/nmat3355
The sustained release of both hydrophilic and hydrophobic immunomodulators for metastatic melanoma by nanoscale liposomal polymeric gels administered intratumorally or systemically is demonstrated. It is also shown that such a co-delivery approach delays tumour growth and increases the survival of tumour-bearing mice, and that its efficacy results from the activation of both innate and adaptative immune responses.

See also: News and Views by Brinker