Twist piezoelectricity: giant electromechanical coupling in magic-angle twisted bilayer LiNbO<sub>3</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38866740.
- Also identified by DOI 10.1038/s41467-024-49321-x and PMC identifier 11169249.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Twisted a pair of stacked two-dimensional materials exhibit many exotic electronic and photonic properties, leading to the emergence of flat-band superconductivity, moiré engineering and topological polaritons. These remarkable discoveries make twistronics the focus point of tremendous interest, but mostly limited to the concept of electrons, phonons or photons. Here, we present twist piezoelectricity as a fascinating paradigm to modulate polarization and electromechanical coupling by twisting precisely the stacked lithium niobate slabs due to the interlayer coupling effect. Particularly, the inversed and twisted bilayer lithium niobate is constructed to overcome the intrinsic mutual limitation of single crystals and giant effective electromechanical coupling coefficient <math xmlns="http://www.w3.org/1998/Math/MathML"> <msubsup><mrow><mi>k</mi></mrow> <mrow><mi>t</mi></mrow> <mrow><mn>2</mn></mrow> </msubsup> </math> is unveiled at magic angle of <math xmlns="http://www.w3.org/1998/Math/MathML"><mn>11</mn> <msup><mrow><mn>1</mn></mrow> <mrow><mo>∘</mo></mrow> </msup> </math> , reaching 85.5%. Theoretical analysis based on mutual energy integrals shows well agreements with numerical and experimental results. Our work opens new venues to flexibly control multi-physics with magic angle, stimulating progress in wideband acoustic-electric, and acoustic-optic components, which has great potential in wireless communication, timing, sensing, and hybrid integrated photonics.