Revealing pair density waves with twist Josephson junctions

We study the Josephson effect for twisted junctions between pair density wave (PDW) superconductors. In the presence of an in-plane magnetic field, the critical current is shown to be maximal at a finite field value, determined by the twist angle and the PDW period. We show that the results are robust to variations in junction geometry and discuss the differences between the pure PDW superconductors and states where a PDW arises as a byproduct of coexistence of superconductivity and charge density waves. Our results establish a potential phase-sensitive probe of PDW correlations at a macroscopic scale.