As far as I know, there isn't a conclusive decent public-key algorithm that is quantum resistent. We know that Diffie Helmann, RSA and their elliptic counterpa

As far as I know, there isn't a conclusive decent public-key algorithm that is quantum resistent. We know that Diffie Helmann, RSA and their elliptic counterparts are broken in quantum. That was essentially all we had. I know that 'lattice based cryptography' is a potential option, and believe there are more potential options. However, as far as I know it is not even clear whether these are safe against classical computers. I should note that I don't know much more about 'lattice based crypto' than the name and the hope it is quantum resistent.