Natural negative refractive index material

Title: Negative Refraction Observed in a Metallic Ferromagnet in the Gigahertz Frequency Range. Abstract: It is generally believed that nature does not provide materials with negative refraction. Here we demonstrate experimentally that such materials do exist at least at GHz frequencies: ferromagnetic metals reveal a negative refraction index close to the frequency of the ferromagnetic resonance. The experimental realization utilizes a colossal magnetoresistance manganite La_2/3Ca_1/3MnO₃ as an example. In this material the negative refractive index can be achieved even at room temperature using external magnetic fields. Phys. Rev. Lett. 98, 197401 (2007)

It is a surprise to find a naturally occurring negative refractive index material. If the material is not so scarce, it could be cheaper to use than fabricated materials. It is promising that it works at room temperature but I wonder how large the magnetic field has to be? The frequency range limit will restrict the uses. Negative refractive index materials can be used to construct superlenses that have a much higher resolution compared to the wavelength used. I can see this being useful in medical imaging devices and possibly photolithography to make ever smaller computer chips.

Better solar energy harnessing?

Harnessing solar energy is a great way to reduce our dependence on other forms of energy. But the current efficiencies and costs are not too attractive. Could mimicking the way the plants harness energy (photosynthesis) be the answer? Some new insights showing a connection with quantum behaviour have been discovered (Nature 446 782). I do hope this is a useful step in finding more efficient ways to harness solar energy and leading to more cost effective manufacture.

Predicting solar activity

Predicting solar activity can be useful when you consider the disruption it causes to the communication systems. More in (Phys. Rev. Lett. 98 131101).

Infrared light for non-invasive scan

The infrascanner by Infrascan Inc. is a very simple device that uses infrared light to scan a surface injury like brain hematomas. This will be useful for paramedics to ascertain the injury or at hospitals that cannot afford more accurate but expensive equipment.

Organic nanowire spin valves with long spin relaxation times

I have not had the time to look into this but it appears that these spin valves could be useful in a quantum computer. If the spin relaxation time of 1 second is equivalent to the coherence time, it is long enough for a decent number of quantum computations. (Nature Nanotechnology 2, 216)

Non-invasive surgery using MRI

Non-invasive surgery can be conducted using magnetic resonance imaging by controlling the movement of a metal bead within the body. (App. Phys. Lett. 90 114105). This is not really marketable but it is nice to see physics in action within the medical field.

Better earthquake understanding?

From PhysicsWeb article:

In 1926, Russian physicist Yakov Frenkel proposed a theory that put a limit on the amount of stress a perfect crystal can withstand before its structural planes begin to slip over one another. Now, however, physicists from Norway have made a theoretical model showing that before Frenkel's limit is ever reached, crystals will deform due to a process called "thermal runaway" -- whereby strain and heat amplify rapidly. This could shed light on the mechanisms underlying deep earthquakes, and could help engineers to determine material tolerances more accurately
(Phys. Rev. Lett. 98 095504).