This one? https://www.railengineer.co.uk/slab-track-paving-the-p-way/ How does this make the rails less likely to buckle? Just because it's held in place more tightly?
https://www.ejrcf.or.jp/jrtr/jrtr15/f38_tec.html
I found the above, but it doesn't say that much about buckling. I don't think they use slab tracks however.
If buckling is the lateral movement of the track due to thermal expansion, I would imagine the old wooden sleepers would be much easier to pull sideways. Looking at the above link about slab tracks, they look far more secure and less likely to move sideways.
https://railroadrails.com/information/what-is-railway-ballas...