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Updated: Jun 22, 2025

Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
Electrically tunable giant Nernst effect in two-dimensional van der Waals heterostructures
Gabriele Pasquale1,2, Zhe Sun1,2, Guilherme Migliato Marega1,2
1Institute of Electrical and Microengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Abstract:
The Nernst effect, a transverse thermoelectric phenomenon, has attracted significant attention for its potential in energy conversion, thermoelectrics and spintronics. However, achieving high performance and versatility at low temperatures remains elusive. Here we demonstrate a large and electrically tunable Nernst effect by combining the electrical properties of graphene with the semiconducting characteristics of indium selenide in a field-effect geometry. Our results establish a new platform for exploring and manipulating this thermoelectric effect, showcasing the first electrical tunability with an on/off ratio of 103. Moreover, photovoltage measurements reveal a stronger photo-Nernst signal in the graphene/indium selenide heterostructure compared with individual components. Remarkably, we observe a record-high Nernst coefficient of 66.4 μV K-1 T-1 at ultralow temperatures and low magnetic fields, an important step towards applications in quantum information and low-temperature emergent phenomena.
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