Fully Electrical Read-Write Device Out of a Ferromagnetic Semiconductor

Phys. Rev. Lett. 106, 057204 (2011) [4 pages]

S. Mark, P. Dürrenfeld, K. Pappert, L. Ebel, K. Brunner, C. Gould, and L. W. Molenkamp

URL: http://link.aps.org/doi/10.1103/PhysRevLett.106.057204

DOI: 10.1103/PhysRevLett.106.057204

 

We report the realization of a read-write device out of the ferromagnetic semiconductor (Ga,Mn)As as the first step to a fundamentally new information processing paradigm. Writing the magnetic state is achieved by current-induced switching and readout of the state is done by the means of the tunneling anisotropic magnetoresistance effect. This 1 bit demonstrator device can be used to design an electrically programmable memory and logic device.

The birth of topological insulators

Joel E. Moore^1,2
Nature 464, 194-198 (11 March 2010) | doi:10.1038/nature08916;


Certain insulators have exotic metallic states on their surfaces. These states are formed by topological effects that also render the electrons travelling on such surfaces insensitive to scattering by impurities. Such topological insulators may provide new routes to generating novel phases and particles, possibly finding uses in technological applications in spintronics and quantum computing.

http://www.nature.com/nature/journal/v464/n7286/full/nature08916.html

What is Watson?

Using advanced computing and emerging technology, IBM is building a natural language processing computer code-named Watson to compete in the game show Jeopardy.

High-Resolution Transmission Electron Microscopy Study of Electrically-Driven Reversible Phase Change in Ge2Sb2Te5 Nanowires

Yeonwoong Jung, Sung-Wook Nam, and Ritesh Agarwal*


Nano Lett., Article ASAP

DOI: 10.1021/nl104537c

By combining high-resolution transmission electron microscopy (HRTEM) characterization and electrical measurements on a unique device platform, we study the reversible electrically-driven phase-change characteristics of self-assembled Ge₂Sb₂Te₅ nanowires. Detailed HRTEM analyses are used to correlate and understand the effect of full and intermediate structural transformations on the measured electrical properties of the nanowire devices. The study demonstrates that our unique approach has the potential to provide new information regarding the dynamic structural and electrical states of phase-change materials at the nanoscale, which will aid the design of future phase-change memory devices.

02 February - Nanopipettes for Metal Transport

Peiman will present the following paper:

Nanopipettes for Metal Transport

      K. Svensson¹, H. Olin², and E. Olsson¹ 

Phys. Rev. Lett. 93, 145901 (2004) [4 pages]

Here we demonstrate, for the first time experimentally, a nanopipette action for metals using multiwalled carbon nanotubes. The process relies on electromigration forces, created at high electron current densities, enabling the transport of material inside the hollow core of carbon nanotubes. In this way nanoparticles of iron were transported to and from electrically conducting substrates.

Light-driven nanoscale plasmonic motors

When Sir William Crookes developed a four-vaned radiometer, also known as the light-mill, in 1873, it was believed that this device confirmed the existence of linear momentum carried by photons¹, as predicted by Maxwell's equations. Although Reynolds later proved that the torque on the radiometer was caused by thermal transpiration², researchers continued to search for ways to take advantage of the momentum of photons and to use it for generating rotational forces. The ability to provide rotational force at the nanoscale could open up a range of applications in physics, biology and chemistry, including DNA unfolding and sequencing^{3, 4, 5, 6} and nanoelectromechanical systems^7, 8, 9,10. Here, we demonstrate a nanoscale plasmonic structure that can, when illuminated with linearly polarized light, generate a rotational force that is capable of rotating a silica microdisk that is 4,000 times larger in volume. Furthermore, we can control the rotation velocity and direction by varying the wavelength of the incident light to excite different plasmonic modes.

Nature Nanotechnology

 

5,

 

570–573

 

(2010)

 

doi:10.1038/nnano.2010.12

Quantum computing

The next big thing in computing is very small. Professor Michelle Simmons (UNSW) explains quantum computing.