Volume 7 Issue 11, November 2012

Biological motors and pumps are equilibrium devices that couple chemical, electrical and mechanical processes in an environment that is far from equilibrium. Recognition of the key role played by microscopic reversibility in their operation is a first step towards rational design of artificial molecular devices.

Stiffness measurements of tumour biopsies and single cells show unique fingerprints that identify the different stages of cancer.

A single layer of graphene can be used as a tunnel barrier for spin injection in silicon with several advantages over other materials that have previously been used.

The conductivity of a single graphene nanoribbon can be measured by lifting the nanoribbon off a surface with the tip of a scanning tunnelling microscope.

Direct determination of carrier concentration and doping in a single nanowire is achieved by placing four electrical contacts along its sidewall.

Many experiments have demonstrated that the spin direction of an electron survives for a relatively long time in an organic material. Results presented at a recent conference show how such long spin-lifetimes can be used in devices.

Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.

The conductance properties of a narrow graphene nanoribbon are correlated with its electronic states over a wide range of bias voltages using a scanning tunnelling microscope.

Hall effect measurement set-up on a single core–shell semiconductor nanowire enables spatially resolved determination of carrier concentration and mobility in the nanowire shell.

Photocurrent microscopy on suspended vanadium dioxide nanobeams reveals the thermal origin of the photoresponse in materials with strong electron–electron and electron–phonon correlations.

Selective molecular sieves can be created from porous, micrometre-sized graphene membranes using oxidative etching.

Current models used for estimating cell stiffness from atomic force microscopy measurements generally overestimate it. Now, an analytical correction for these models enables the cell stiffness to be estimated more accurately, and improves the use of atomic force microscopy as a diagnostic tool in cancer.

Spin can be injected into silicon from a ferromagnetic contact and across a graphene barrier with resistance-area products up to one thousand times lower than with comparable oxide tunnel barriers.

The efficiency of solar cells with high-area, nanostructured surfaces is limited by surface and Auger charge-recombination processes, which can be slowed through appropriate levels of junction doping.

In situ transmission electron microscopy can be used to study the dynamic lithiation of single-crystal silicon with atomic resolution.

Nanomechanical signatures of human breast biopsies obtained using an atomic force microscope show close correlation between softening of cancer cells and progression of cancer.