Autor: |
Makiko Ogino, Yoshihiro Okamura, Kosuke Fujiwara, Takahiro Morimoto, Naoto Nagaosa, Yoshio Kaneko, Yoshinori Tokura, Youtarou Takahashi |
Jazyk: |
angličtina |
Rok vydání: |
2024 |
Předmět: |
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Zdroj: |
Nature Communications, Vol 15, Iss 1, Pp 1-7 (2024) |
Druh dokumentu: |
article |
ISSN: |
2041-1723 |
DOI: |
10.1038/s41467-024-49056-9 |
Popis: |
Abstract Direct conversion from terahertz photon to charge current is a key phenomenon for terahertz photonics. Quantum geometrical description of optical processes in crystalline solids predicts existence of field-unbiased dc photocurrent arising from terahertz-light generation of magnetic excitations in multiferroics, potentially leading to fast and energy-efficient terahertz devices. Here, we demonstrate the dc charge current generation from terahertz magnetic excitations in multiferroic perovskite manganites with spin-driven ferroelectricity, while keeping an insulating state with no free carrier. It is also revealed that electromagnon, which ranges sub-terahertz to 2 THz, as well as antiferromagnetic resonance shows the giant conversion efficiency. Polar asymmetry induced by the cycloidal spin order gives rise to this terahertz-photon-induced dc photocurrent, and no external magnetic and electric bias field are required for this conversion process. The observed phenomena are beyond the conventional photovoltaics in semi-classical regime and demonstrate the essential role of quantum geometrical aspect in low-energy optical processes. Our finding establishes a paradigm of terahertz photovoltaic phenomena, paving a way for terahertz photonic devices and energy harvesting. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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