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DOE OSTI · 2574349

Twist-engineered phonon polaritons in α − V 2 O 5

Shiravi, H. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)] (ORCID:0000000291301612)·Zheng, W. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)]·He, Y. [University of Wisconsin-Madison, WI (United States)]·Ran, S. [Washington University in St. Louis, MO (United States)]·Rhodes, D. A. [University of Wisconsin-Madison, WI (United States)]·Balicas, L. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)]·Zhou, H. D. [University of Tennessee, Knoxville, TN (United States)]·Ni, G. X. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)]
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Abstract

The advent of layered materials has unveiled new opportunities for tailoring electromagnetic waves at the subwavelength scale, particularly through the study of polaritons, a hybrid light–matter excitation. In this context, twist-optics, which investigates the optical properties of twisted stacks of van der Waals (vdW) layered specimens, has emerged as a powerful tool. Here, we explore the tunability of phonon polaritons in α-V 2 O 5 via interlayer twisting using scanning nano-infrared (IR) imaging. We show that the polaritonic response can be finely adjusted by varying their interlayer electromagnetic coupling, allowing for precise control over the propagation direction and phase transition from open unidirectional iso-frequency contours to closed elliptic geometries. Furthermore, our experimental results, in conjugate with theoretical modeling, reveal the mechanisms underpinning this tunability, highlighting the role of twist-induced nano-light modifications for advanced nanophotonic control at the nanoscale.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Shiravi, H. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)] (ORCID:0000000291301612), Zheng, W. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)], He, Y. [University of Wisconsin-Madison, WI (United States)], Ran, S. [Washington University in St. Louis, MO (United States)], Rhodes, D. A. [University of Wisconsin-Madison, WI (United States)], Balicas, L. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)], Zhou, H. D. [University of Tennessee, Knoxville, TN (United States)], Ni, G. X. [Florida State University, Tallahassee, FL (United States); National High Magnetic Field Laboratory, Tallahassee, FL (United States)]. 2025-04-29. Twist-engineered phonon polaritons in α − V 2 O 5. https://doi.org/10.1364/ol.557267

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