Browsing by Author "Tay, Fuyang"

Now showing 1 - 5 of 5
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    Giant terahertz polarization rotation in ultrathin films of aligned carbon nanotubes
    (Optical Society of America, 2021) Baydin, Andrey; Baydin, Andrey; Komatsu, Natsumi; Tay, Fuyang; Ghosh, Saunab; Makihara, Takuma; Noe, G. Timothy; Kono, Junichiro; Kono, Junichiro; Kono, Junichiro; Kono, Junichiro
    For easy manipulation of polarization states of light for applications in communications, imaging, and information processing, an efficient mechanism is desired for rotating light polarization with a minimum interaction length. Here, we report giant polarization rotations for terahertz (THz) electromagnetic waves in ultrathin (∼45nm), high-density films of aligned carbon nanotubes. We observed polarization rotations of up to ∼20∘ and ∼110∘ for transmitted and reflected THz pulses, respectively. The amount of polarization rotation was a sensitive function of the angle between the incident THz polarization and the nanotube alignment direction, exhibiting a “magic” angle at which the total rotation through transmission and reflection becomes exactly 90°. Our model quantitatively explains these giant rotations as a result of extremely anisotropic optical constants, demonstrating that aligned carbon nanotubes promise ultrathin, broadband, and tunable THz polarization devices.
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    Magnetically tuned continuous transition from weak to strong coupling in terahertz magnon polaritons
    (American Physical Society, 2023) Baydin, Andrey; Hayashida, Kenji; Makihara, Takuma; Tay, Fuyang; Ma, Xiaoxuan; Ren, Wei; Ma, Guohong; Noe, G. Timothy; Katayama, Ikufumi; Takeda, Jun; Nojiri, Hiroyuki; Cao, Shixun; Bamba, Motoaki; Kono, Junichiro; Smalley-Curl Institute
    Depending on the relative rates of coupling and dissipation, a light-matter coupled system is either in the weak- or strong-coupling regime. Here, we present a unique system where the coupling rate continuously increases with an externally applied magnetic field while the dissipation rate remains constant, allowing us to monitor a weak-to-strong coupling transition as a function of magnetic field. We observed a Rabi splitting of a terahertz magnon mode in yttrium orthoferrite above a threshold magnetic field of ∼14 T. Based on a microscopic theoretical model, we show that with increasing magnetic field the magnons transition into magnon polaritons through an exceptional point, which will open up new opportunities for in situ control of non-Hermitian systems.
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    Multimode ultrastrong coupling in three-dimensional photonic-crystal cavities
    (Rice University, 2025) Tay, Fuyang; Mojibpour, Ali; Sanders, Stephen; Liang, Shuang; Xu, Hongjing; Gardner, Geoff C.; Baydin, Andrey; Manfra, Michael J.; Alabastri, Alessandro; Hagenmüller, David; Kono, Junichiro; U.S. Army Research Office;The Gordon and Betty Moore Foundation;The W. M. Keck Foundation;The Robert A. Welch Foundation; Applied Physics
    A work investigates multimode ultrastrong coupling between cavity modes of a three-dimensional photonic-crystal cavity and the cyclotron resonance of a Landau-quantized two-dimensional electron gas in gallium arsenide.
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    Observation of colossal terahertz magnetoresistance and magnetocapacitance in a perovskite manganite
    (Optica Publishing Group, 2023) Tay, Fuyang; Chaudhary, Swati; He, Jiaming; Peraca, Nicolas Marquez; Baydin, Andrey; Fiete, Gregory A.; Zhou, Jianshi; Kono, Junichiro; Smalley-Curl Institute
    Terahertz (THz) magnetoresistance effects have been extensively investigated and have shown promising results for applications in magnetic modulations of the amplitude of THz waves. However, THz magnetocapacitance in dielectric systems, which is essential for phase modulations of THz radiation, remains largely unexplored. Here, we study the THz response of a bulk single crystal of L a 0.875 S r 0.125 M n O 3 at around its Curie temperature, observing significant magnetic-field-induced changes in the THz resistance and capacitance extracted from the optical conductivity. We discuss possible mechanisms for the observed coexistence of colossal THz magnetoresistance and magnetocapacitance in a perovskite manganite that is not multiferroic. This work enhances our understanding of colossal magnetoresistance in a complex system with THz spectroscopy and demonstrates potential use of perovskite manganites in THz technology.
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    Terahertz chiral photonic-crystal cavities for Dirac gap engineering in graphene
    (Rice University, 2025-04-22) Tay, Fuyang; Alabastri, Alessandro; Kono, Junichiro; Applied Physics Graduate Program, Smalley–Curl Institute; Department of Electrical and Computer Engineering; Rice Advanced Materials Institute; Department of Physics and Astronomy; Department of Materials Science and NanoEngineering
    A work proposed a scheme to realize terahertz chiral photonic-crystal cavities with broken time-reversal symmetry and investigated the Dirac gap opening in graphene when coupled to the chiral cavities.