Topological Quantum Electronics and Optoelectronics in Moire Superlattices
Abstract
In quantum materials, quasiparticles are constrained by an emergent quantum geometry, which originates from the local geometrical structure of quantum wavefunctions. These quantum geometrical properties, often characterized as Berry phase and Berry curvature, capture the coherences between orbitals, atomic positions, and spins within the unit cells, connect deeply to the topology of materials, and can strongly modify the manifestations of electromagnetism in materials. Remarkably, despite their pure quantum nature, Berry phase and topology can persist at ambient conditions in macroscopic materials and are robust to defects, local perturbations and decoherence. Extensive research over the past decade has discovered topology and Berry phase in a vast array of materials, ranging from insulators and metals, to magnets and even superconductors. However, the way quantum geometry affects their electromagnetic responses remains largely unknown. We propose a collaborative research project to investigate novel electromagnetism enabled by topology and quantum geometry in quantum moiré superlattices. This new class of atomically-thin materials are highly tunable with in-situ electrical gating, and host versatile topological and quantum geometrical properties. Moreover, these moiré systems can exhibit unconventional superconductivity, spontaneous symmetry breaking and other correlated effects. These can coexist and intertwine with topology and quantum geometry, giving rise to even more exotic electromagnetic responses. In this proposal, we will design and build high-quality moiré lattices through layer-by-layer assembly. We then combine precision electronic transport techniques with versatile optical probes to explore unconventional photovoltaics, electrical rectification and multiferroic memory effects that emerge from Berry phase and topology in moiré superlattices. We also develop new tools to probe the quantum geometrical effects in moiré lattices under non-equilibrium and at the nanometer scale. Our proposal may lead to the realization of new generation electronic, optical, magnetic, and memory devices that can harness robust quantum properties for urgent energy, sensing, communications and computation needs.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 21, 2022
- Source ID
- FA95502110319XX0
Entities
People
- Pablo Jarillo-Herrero
Organizations
- Air Force Office of Scientific Research
- Massachusetts Institute of Technology
- United States Air Force