Phys.org November 10, 2021
Researchers in China developed a highly efficient magneto-tunable and phonon-based monochromatic THz generator with a frequency of ~0.9 THz using a 2D ferromagnetic Cr2Ge2Te6 crystal. They combined theoretical and experimental approaches and innovatively exploited the excellent properties of its van der Waals interlayered breathing phonon mode (boson) with THz-TDS (time domain spectroscopy) magneto-optic system. They found the breathing mode could effectively couple with incident co-frequency THz pulse and form a phonon-polariton. This quasi-bosonic particle could then generate far-field electro-magnetic radiation with monochromatic frequency comparable to the phonon mode. They regulated the radiation via the spin-phonon interaction channel. The phonon-related THz radiation could also be effectively modulated by external magnetic fields. The work provides a novel strategy for the realization of new THz sources…read more. Open Access TECHNICAL ARTICLEÂ
Terahertz responses of Cr2Ge2Te6 crystal…Credit: Advanced Science, 29 October 2021Â