I dont know what defines a 6th gen but their technology in A.I. seems to be pretty good up there because they do have a stealth drone that is bigger than the rest and the one that actually test fired weapons like glide bombs. Some U.S. companies rely and acknowledge them to be ahead of this field and of course plenty of ground drone projects that are operational. I also see their country is always 1st place on International Collegiate Programming Contests and I am sure skills in programming is heavily needed.
They are making hypersonic aircraft projects. https://www.militarynews.ru/story.asp?lang=RU&nid=516338&rid=1
"Roscosmos is developing radiolucent heat-shielding materials for radomes for hypersonic aircraft, according to the materials of the State procurement portal.
According to the materials of the portal, the state corporation is looking for a contractor for "developing a technology for manufacturing radiotransparent heat-protective materials for fairings of hypersonic aircraft based on volumetric frames made of refractory continuous fibers." The research work was called "Thor".
Work should be completed by September 2020. They allocated 346.9 million rubles.
There were references of mach 4 or 5 for the mig-41 but again I do not know if hypersonic or near hypersonic speeds is a prerequisite to be a 6th gen fighter.
There was alot of talk of photonic radars excluding Russia since I already made it more than clear on the Su-57 thread where they are at. https://phys.org/news/2014-03-fully-photonics-based-laser.html
"team of researchers in Italy has developed the first fully photonics-based coherent radar system. In their paper published in the journal Nature, the team describes how they built their new radar system and what it might mean for the future of radar systems. Jason McKinney of the US Naval Research Laboratory offers a News & Views perspective piece on the development of the radar system in the same issue and outlines issues involved with attempting to implement such a system into real world applications"
The radar system the team built is still just a prototype, though it does appear feasible. The team tested its abilities by monitoring real aircraft taking off at a nearby airport and then comparing what they observed with data from traditional electronic signal based systems. They report that the systems matched very closely. That of course is just an initial test, as McKinney notes, much more research and testing will need to be done before the researchers will know if such a system could provide better results than conventional systems. Also, another area of concern is range, which could impact jitter, and thus the accuracy of the system.
The timeline of photonic radar announcements were not that far apart upon Italy and Russia's discovery, but the news reports I have been receiving from Russia seem more consistent and up to date with plans of production. So far Russians have also made announcements that their photonic radars exceed conventional radars while here of course we have not seen the same thing since the US claims they have the same issues as the Italians who have not provided better results than conventional radars. Raytheon has plans as well https://news.arizona.edu/press-release/ua-selected-photonics-project
. This might be considered a 6th gen radar requirement.