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Comment Re:questions from a biologist (Score 2, Informative) 70

There are a lot of different types of quantum dots. Some are colloidal (dots in a liquid) - others are buried or built into materials. The fluorescent dots that you are familiar with are the colloidal ones; some are made of CdSe, ZnSe, etc, and being in a liquid medium, of course they are injectable and can be used as biological fluorescent markers. In terms of color of light emitted, the bulk material emits at some characteristic color. With QDs, as you change their size, the light emitted changes color, even though you're using the same material. Larger dots emit at a longer wavelength (redder), smaller dots at higher wavelengths (bluer).

The other type of quantum dots, the ones with photovoltaic/electronic applications, tend to be dots that are buried or grown into another solid material. The "dots" that this researcher has created are of this type - basically it seems he's managed to create individual silicon atoms on a surface that have dangling bonds in a sea of non-dangling-bond Si. The fact that the dangling bond Si atoms are far-separated from each other makes them maintain their atomic energy levels instead of having their energy levels develop into bands, as what happens in typical crystalline material. It seems like these dots were developed for quantum computing purposes and are concerned with the wave functions of the electrons, as opposed to light emission and band gap energies.

Comment Wouldn't exactly call it a quantum dot (Score 1) 70

As someone who works with typical quantum dots, I find Wolkow's research interesting, but I wouldn't necessarily call what he's created a "quantum dot." Usually we are concerned with the bandgap shifting that is possible by changing the size of the dot. As I interpret his paper, it seems he's managed to create individual dangling-bond Si atoms surrounded by Si terminated by H. These dangling-bond states *handwaving explanation* seem to remain with quantized energy states instead of acting like the bulk material they're surrounded by, which have energy bands. It seems like he's interested more in electron tunneling effects for quantum computing rather than bandgap size manipulation. Maybe I'm just old-fashioned in how I think about quantum dots :p

IT Job Market Is Tanking, But Not For Everyone 371

CWmike writes "Shortly after the COO of Automated HealthCare Solutions learned that Microsoft planned to cut 5,000 workers over the next 18 months, he and another employee of the medical services provider flew out to Redmond. AHCS now has more than 100 resumes, some of them from Microsoft employees, for about a dozen open positions. That's how the tech job market is these days: there's no doubt the market is tanking, but not for everyone. While numerous IT vendors are laying off workers, and corporate IT jobs are being lost as well, plenty of companies are still hiring. Microsoft's careers site lists more than 700 open jobs in the US, both technical and administrative positions. And IBM has about 3,200 jobs and internships listed worldwide, more than 550 of them in the US — even as it cuts thousands of workers in a move that it is describing not as a layoff, but an effort to 'match skills and resources with our client needs."

Comment Re:Elimitate upselling (Score 1) 1367

Off-topic: Damn! I just used my last mod point! I would mod you Overrated just to prove that I really DON'T have a penis :p

Truthfully, I totally agree with you on the marijuana culture issue - at least within the sphere of universities, which is where most of us Slashdotters probably encounter it. However, it does depend on where you are - sometimes the people selling marijuana DO also sell harder drugs, too (my boyfriend worked in Hawaii for a while, the latter was the case there).

Comment This is news? (Score 4, Insightful) 683

This is news? I thought that this idea has been around for a while, or at least it was the logical conclusion of having a multiverse. A livable universe doesn't exist "just for us," it just so happens that out of all of them, at least one of them would end up hospitable. Kind of like planets and solar systems.

FCC Unanimously Approves White Space Wi-Fi 156

Smelly Jeffrey writes "With the release of this whitepaper, the FCC unanimously approved plans for a new technology with strong supporters and even stronger detractors. White Space Wi-Fi effectively allows manufacturers of wireless devices to incorporate transceivers that operate on unused DTV channels. Although the deregulation is new, the idea seems to have caught Google's interest recently as well. It seems that this has been rather rushed through the normally stagnant channels at the FCC. While some view it as interference in the already crowded spectrum, it seems the FCC Chairman really likes the idea of re-purposing dark parts of the newly allocated DTV bands once more." Update: 11/06 18:15 GMT by T : You may want to look at Tuesday's mention of the decision as well, but the additional links here are interesting.

Schneier on Security Screenshot-sm 204

brothke writes "There is a perception in both the private and government sector, that security, both physical and digital, is something you can buy. Witness the mammoth growth of airport security products following 9/11, and the sheer number of vendors at security conferences. With that, government officials and corporate executives often think you can simply buy products and magically get instant security by flipping on the switch. The reality is that security is not something you can buy; it is something you must get." Keep reading for the rest of Ben's review.