Recently, topological semimetals have emerged as strong candidates for solid
state thermomagnetic refrigerators due to their enhanced Nernst effect. This
enhancement arises from the combined contributions of the Berry curvature
induced anomalous Nernst coefficient associated with topological bands and the
normal Nernst effect resulting from synergistic electron-hole compensation.
Generally, these two effects are intertwined in topological semimetals, making
it challenging to evaluate them independently. Here, we report the observation
of high Nernst effect in the electron hole compensated semimetal ScSb with
topologically trivial electronic band structures. Remarkably, we find a high
maximum Nernst power factor of $PF_N \sim 35 \times 10^{-4}$ W m$^{-1}$
K$^{-2}$ in ScSb. The Nernst thermopower ($S_{xy}$) exhibits a peak of $\sim$
47 $\mu$V/K at 12 K and 14 T, yielding a Nernst figure of merit ($z_N$) of
$\sim 28 \times 10^{-4}$ K$^{-1}$. Notably, despite its trivial electronic band
structure, both the $PF_N$ and $z_N$ values of ScSb are comparable to those
observed in topological semimetals with Dirac band dispersions. The origin of
the large Nernst signal in ScSb is explained by well compensated electron and
hole carriers, through Hall resistivity measurements, angle-resolved
photoemission spectroscopy (ARPES) and density functional theory (DFT)
calculations.

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