| Autor: |
Yao, Yuanzhao, Ikeda, Naoki, Chalimah, Siti, Kuroda, Takashi, Sugimoto, Yoshimasa, Mano, Takaaki, Koyama, Hiromi, Hashimoto, Rei, Kaneko, Kei, Kakuno, Tsutomu, Ookuma, Shinji, Togawa, Ryuichi, Ohno, Hiroshi, Saito, Shinji, Takahashi, Naoki, Tanimura, Hirotaka, Takagi, Shigeyuki, Sakoda, Kazuaki |
| Zdroj: |
Japanese Journal of Applied Physics; May2022, Vol. 61 Issue 5, p1-8, 8p |
| Abstrakt: |
We fabricated surface-emitting quantum cascade lasers with photonic crystal resonators whose active layers were strain-compensated InGaAs/AlInAs multiple quantum wells to operate at 4.3 ÎĽ m. We tested two kinds of square-lattice photonic crystals consisting of circular and pentagonal InGaAs cylinders as a unit structure. We examined their output power and far-field pattern to find that both of them were improved by lowering the photonic-crystal symmetry to achieve a high extraction efficiency. The maximum output power was 50 mW at 77 K and the far-field pattern was a single peak with a divergence angle smaller than 1° for the pentagonal cylinder structure. In addition, we attributed the lasing mode to a B2-symmetric (quadrupole) eigenstate on the Î" point for the circular cylinder structure by observing the polarization dependence of the far-field pattern and comparing it with calculations by the k · p perturbation method. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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