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arXiv · 2105.08264

Highly efficient terahertz generation using 3D Dirac semimetals

Lu Wang·Jeremy Lim·Liang Jie Wong
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Abstract

We show that 3D Dirac semimetals are promising candidates for highly efficient optical-to-terahertz conversion due to their extreme optical nonlinearities. In particular, we predict that the conversion efficiency of Cd3As2 exceeds typical materials like LiNbo3 by >5000 times over nanoscale propagation distances. Our studies show that even when no restrictions are placed on propagation distance, Cd3As2 still outperforms LiNbo3 in efficiency by >10 times. Our results indicate that by tuning the Fermi energy, Pauli blocking can be leveraged to realize a step-like efficiency increase in the optical-to-terahertz conversion process. We find that large optical to terahertz conversion efficiencies persist over a wide range of input frequencies, input field strengths, Fermi energies, and temperatures. Our results could pave the way to the development of ultrathin-film terahertz sources for compact terahertz technologies.

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Lu Wang, Jeremy Lim, Liang Jie Wong. 2021-05-18. Highly efficient terahertz generation using 3D Dirac semimetals. https://arxiv.org/abs/2105.08264

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