Solid-State UV Lamp Built
That range of frequencies above violet light is known to have many uses, from illuminating biological materials to causing some colors to pop on clothing and in paint. At the right frequencies it can also be used to kill bacteria, but the sources needed for that have many issues. As reported by the American Institute of Physics, researchers in Japan have developed the first solid-state UV phosphor that can produce the photons of the needed frequencies.
The UV sources that can kill bacteria are called vacuum UV lights because the photons can travel far in a vacuum, but are quickly stopped in the air. The reason they are stopped is because they react with oxygen atoms, creating very reactive oxygen radicals. Those radicals are actually what destroy bacteria. Producing light at the vacuum UV frequencies though is difficult and current sources run hot, do not last long, and are not very efficient. Using thin films of potassium, magnesium, and fluorine (KMgF3) the researchers were able to create a much more efficient vacuum UV lamp that will also be cheaper to produce.
Another benefit to using the KMgF3 source is that it is a much safer material to produce, compared to those used in traditional sources. The fluoride compound however is toxic and corrosive, but the researchers found a means to safely fabricate it, using pulsed laser deposition.