We just published a paper finally demonstrating that TiSe2 contains a Bose condensate of excitons. The experimental signature is a soft plasmon that falls to zero frequency at Tc. Bert Halperin and Maurice Rice nicknamed this phase “excitonium” in their 1968 Rev. Mod. Phys. paper to emphasize the physical picture of an exciton condensate as an electronic crystal. This discovery, which we believe should be viewed as a landmark in our field, was done using our new M-EELS technique (see Sean’s paper, below).
The media frenzy over this discovery has been unreal, surpassing our wildest expectations. Some of the better written articles may be found in Newsweek, The Independent, and the The Daily Mail. Here is a polished video on YouTube.
Here’s a link to the article in Science.