It's probably something proprietary and I doubt it's anything fancy hence why they give them marketing names like "Quantum CPU" to make them sound impressive, your best bet would be to open a TV up and look at the markings on the chip but I wouldn't recommend it.
I don't believe that they make custom chips for TV's. On all TV's with Android it is easy to identify CPU's inside because of various apps on the Android that can read those info but problem is with Tizen OS, there are no such apps. Yes, one way it can be identified if someone open TV and that's why I'm asking, probably someone already done that around the world, that's why we have forums or simply someone have info what CPU model is inside via some other methods.
I would like to know exact CPU model so that I can better compare various TV models. This info is missing.
I don't think you'll be able too as Samsung do not release any details of the CPU's used wthin their TV's aside from their commercial names. It's not like they are like Intel or AMD processors and Samsung use pretty much the same one's as found in phones. Thus I guess a cross reference could be performed.
Some info here Neo Quantum Processor in Samsung TVs what is it | but I think you're out of luck with this one unless someone in this forum knows better...
Looking into this a bit harder, it may be that they use Mediatek chips. Certainly Samsung is going to use the Mediatek S900 chip in its 8K TVs in the future. I cannot find out for certain what they have used up to now, but I read somewhere that they have used MStar TV SOCs. MStar is now a subsidiary of Mediatek.
Found this quote from 2020:
“The SoCs for Samsung Electronics TVs are loaded with central processing units (CPUs), graphic processing units (GPUs) and neural network processing units (NPUs), and these SoCs can be found only in Samsung TVs,” said Kim Hyun-seok, head of the CE Division
This suggests that they do not use an off-the-shelf microchip. However it is not clear where it is manufactured.