The first evidence for phenomena related to the Aharonov–Bohm effect in CDWs was reported in a 1997 paper, which described experiments showing oscillations of period h /2 e in CDW (not normal electron) conductance versus magnetic flux through columnar defects in NbSe 3. Later experiments, including some reported in 2012, show oscillations in CDW current versus magnetic flux, of dominant period h /2 e, through TaS 3 rings up to 85 μm in circumference above 77 K. This behavior is similar to that of the superconducting quantum interference device (see SQUID), lending credence to the idea that CDW electron transport is fundamentally quantum in nature (see quantum mechanics).