Combinatorics

Physics

Electrode

Nernst equation

Topology (electrical circuits)

Energy (signal processing)

Transversal (combinatorics)

Mathematics

Nernst effect

Seebeck coefficient

Mathematical analysis

Materials science

Thermoelectric materials

Condensed matter physics

Quantum mechanics

Electrical resistivity and conductivity

Thermoelectric effect

Thermodynamics

Physical review. B./Physical review. B

Thermoelectric materials can recover electrical energy from waste heat and vice versa, which are of great significance in green energy harvesting and solid state refrigerators. The thermoelectric figure of merit ($z\mathrm{T}$) quantifies the energy conversion efficiency, and a large Seebeck or Nernst effect is crucial for the development of thermoelectric devices. Here we present a significantly large Nernst thermopower in topological semimetal ${\mathrm{ZrTe}}_{5}$, which is attributed to both strong Berry curvature and bipolar transport. The largest in-plane ${S}_{xy}$ (when B//b) approaches 1900 $\ensuremath{\mu}\mathrm{V}/\mathrm{K}$ at $T=100$ K and B = 13 T, and the out-of-plane ${S}_{xz}$ (when B//c) reaches 5000 $\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{V}/\mathrm{K}$. As a critical part of ${z}_{N}\mathrm{T}$, the linearly increased in-plane ${S}_{xy}$ and resistivity ${\ensuremath{\rho}}_{\mathrm{yy}}$ in regard to B induces an almost linear increasing transversal ${z}_{N}\mathrm{T}$ without saturation under high fields. The maximum ${z}_{N}\mathrm{T}$ of 0.12 was obtained at B = 13 T and $T=120$ K, which significantly surmounts its longitudinal counterpart under the same condition.

Giant Nernst effect and field-enhanced transversal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>z</mml:mi><mml:mi>N</mml:mi></mml:msub><mml:mi mathvariant="normal">T</mml:mi></mml:math> in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">ZrTe</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:math>

Giant Nernst effect and field-enhanced transversal zNT in ZrTe5