Exploring metastability via third harmonic measurements in single crystals of 2H-NbSe<SUB>2</SUB> showing an anomalous peak effect

We explore the metastability effects across the order-disorder transition pertaining to the peak effect phenomenonon in critical current density (Jc) via the first and the third harmonic ac susceptibility measurements in the weakly pinned single crystals of 2H-NbSe2. An analysis of our data suggests that an imprint of the limiting (spinodal) temperature above which Jc is path independent can be conveniently located in the third harmonic data (x3&#969;')