MIT news article about it: https://news.mit.edu/2016/nanophotonic-incandescent-light-bu...
I think this paper follows the same basic principle and idea.
However the progress made from the very primitive device described by MIT and the high-performance prototype made by the Chinese team has been huge.
The Chinese have used completely other materials, which enabled also a long lifetime, not only a better efficiency. There are many new constructive details which contribute to an increased efficiency. The design methodology used by the Chinese for the lossless optical filter is far more advanced and it enabled a much better filter with much less layers.
The MIT article showed an interesting idea, for which it was not clear if it can be successful in practice, while this shows a real device that needs only minor changes in order to become suitable for mass production (e.g. the replacement of HfO2 with TiO2 in the window coating and the replacement of the O-ring used in the prototype with hermetic glass-alumina bonding).
This device could be easily converted into a commercial product in a couple of years.