pV

picovolt

Voltageexact by definition

The picovolt is 10⁻¹² of a volt. It is the resolution floor of the best nanovoltmeters and of SQUID-based null detectors, and the scale at which a Josephson array standard is compared against a working reference. The factor is exact, being an SI prefix.

Watch out: Nothing at this level survives an ordinary connector. A single junction of dissimilar metals with a millikelvin of temperature difference across it produces more thermal EMF than the signal, which is why picovolt work uses matched copper joints, thermal shielding and a reversing switch that cancels the offset.

1 pV 1.0000000e-12 V