Nature Physics 12, 568–572 (2016); published online 2 May 2016; corrected after print 2 September 2016

In the version of this Letter originally published ref. 34 was not updated and should have read: Gingrich, E. C. et al. Controllable 0-π Josephson junctions containing a ferromagnetic spin valve. Nature Phys. 12, 564–567 (2016). This has now been corrected in the online versions of the Letter.