IBM research says "Lattice-based cryptography is complex cryptographic scheme designed to protect data from the threat of crypto-breaking by fault-tolerant universal quantum computers with millions of qubits. Such a system is still many years away, but with lattice cryptography we will be ready". We'll have to wait and see.
Meanwhile here's the details - https://www.research.ibm.com/5-in-5/lattice-cryptography/