Earlier today a team of scientists at Stanford University have reported that they have solved the problem of Rudolph the Reindeer's glowing nose and may have found new insight into the problem of Santa Claus and Santa sightings. 

During a routine scanning electron microscope inspection of their doomed samples, the researchers saw something they had not seen before. An approximately 40 micron Santa and 130 micron Rudolph appeared on the sample. They apparently thought that the chimney in the Stanford Nanofabrication facility was a standard house chimney. Overpowered by Chlorine fumes from the leaky system, Santa and Rudolph passed out and somehow (presumably by more leaks) made their way into the vacuum system of the Raith 150 Electron Beam Lithography tool, where they were unfortunately permanently impressed into the researchers' chip. The reasearchers, after overcoming their shock and grief, decided to inspect Santa and Rudolph at the nanometer scale. The image below shows their resuls.

In panel A one clearly sees Santa and Rudolph. Santa was measured to be approximately 40 microns in height and Rudolph at a whopping 130 microns. A closeup of Rudolph's nose B reveals an interesting feature, which is shown in C to be a Photonic Crystal cavity.

Rudolph's nose is apparently equipped with a photonic crystal cavity, which is a novel nano-scale light emitting device. Judging by the lattice constant of 250 nm and hole radius of 140 nm, the nose emits signals in the infrared around 950 nm, and serves most likely as a communication device. This wavelength is close to that used in Local Area Networks and may have been chosen to avoid absorption and scattering losses. This somewhat validates the "red glowing nose" theory of the reindeer, however, makes much more sense from a communications standpoint and compatibility with current communication infrastructure. Lasing has not been verified, but researchers will do so in future experiments.

 Finally, the contents of Santa's bag could not be identified. However, researchers believe that there is no one Santa. Rather it is an army of micron sized Santas that assemble the gifts in place. This may shed new light on the "how fast would Santa have to travel" dilemma, and provide new insight and tools into nanofabrication.

 All questions about Santa, and inquiries about collection of his remains should be addressed to Ilya Fushman (ifushman at stanford dot edu).

Controlling cavity reflectivity with a single quantum dot

The paper can be found here: http://www.nature.com/nature/journal/v450/n7171/full/nature06234.html 
See also the Q&A article by Dirk Englund  here.  

This article is meant to give an introduction to the technology of Photonic Crystals (PC's) and how they can be applied to quantum information processing on the chip. Photonic crystals offer a highly versatile platform for manipulation of light and an unprecedented degree of control over light matter interaction on a chip. [2] The development of this technology has come along in two main avenues. The first is the development of tools for controlling light on a chip with a focus on systems level integration for optical communication and optical signal processing. The second is the development of tools for strong interactions between light and matter, where the focus has been on single elements of an optical network that can be used to enhance quantum effects, such as getting more light out of emitters. We review work along both of these avenues and show that they can come together to realize a quantum information processing device in solid state. There are many challenges which need to be overcome in order to realize useful devices. Luckily, developments in PC's for optics and communication can be directly transferred to quantum information processing devices at a system level, which is where this research will head in the next years. On the quantum side, a breakthrough in material science and manipulation of "atoms" inside these chips will be needed in order to realize a quantum memory and stable quantum bits.