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Ferroelectricidad acoplada y superconductividad en la doble capa Td-MoTe2
Apoorv Jindal1, Amartyajyoti Saha2,3, Zizhong Li4
1Department of Physics, Columbia University, New York, NY, USA.
Nature
|January 4, 2023
Resumen
Los investigadores demuestran que la bicapa Td-MoTe2 exhibe tanto ferroelectricidad como superconductividad. Se observa una transición impulsada por el campo entre los estados superconductores y normales en el punto de transición ferroeléctrico, que ofrece un nuevo control sobre las fases cuánticas.
Área de la Ciencia:
- Física de la materia condensada
- Ciencias de los materiales cuánticos
Sus antecedentes:
- La superconductividad es sintonizable por dopaje electrostático en varios materiales 2D.
- Algunos materiales 2D con estructuras cristalinas polares exhiben ferroelectricidad, lo que permite el control de la polarización a través de campos eléctricos.
Objetivo del estudio:
- Investigar la coexistencia y la interacción de la ferroelectricidad y la superconductividad en la bicapa Td-MoTe2.
- Para explorar el control electrostático de las propiedades superconductoras de este material.
Principales métodos:
- Síntesis experimental y caracterización de la bicapa Td-MoTe2.
- Mediciones de transporte eléctrico para detectar la superconductividad y la conmutación ferroeléctrica.
- Variación sistemática de la densidad del portador y de los campos eléctricos.
Principales resultados:
- Bilayer Td-MoTe2 exhibe una conmutación ferroeléctrica y una superconductividad simultáneas.
- Una transición de primer orden inducida por el campo desde el estado superconductor al estado normal ocurre en la transición ferroeléctrica.
- La temperatura de transición superconductora (Tc) muestra un máximo con densidad de portador y polarización controladas.
- El máximo Tc se correlaciona con las densidades de portadores de electrones y agujeros compensados.
Conclusiones:
- Bilayer Td-MoTe2 es un nuevo superconductor bidimensional sensible a la polarización.
- Los fenómenos observados sugieren un mecanismo de emparejamiento entre bandas impulsado por bolsas de Fermi anidadas.
- Este sistema ofrece una nueva plataforma para el control electrostático de las fases cuánticas.
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