Low-loss Sb$_2$S$_3$ Optical Phase Shifter Enabled by Optimizing Sputtering Conditions

Yuto Miyatake; Tomohiro Anda; Yosuke Wakita; Kotaro Makino; Shogo Hatayama; Makoto Okano; Kasidit Toprasertpong; Shinichi Takagi; Mitsuru Takenaka

paper

Low-loss Sb $_{2}$ S $_{3}$ Optical Phase Shifter Enabled by Optimizing Sputtering Conditions

arXiv:2505.10752

Abstract

By quantitatively evaluating the atomic concentrations of sputtered Sb $_{2}$ S $_{3}$ films with different sputtering powers and Ar flows, we reveal that a sputtered Sb $_{2}$ S $_{3}$ film becomes close to the stoichiometric composition as the sputtering power and Ar flow decrease. We characterize the optical properties of Sb $_{2}$ S $_{3}$ and show that the lower sputtering power leads to a better figure of merit of Sb $_{2}$ S $_{3}$ as an optical phase shifter in the near infrared (NIR) range. Based on these results, we achieve a loss per phase shift of 0.33 dB/ $I ¨ $ at a wavelength of 1.55 $I^¼$ m, one of the lowest losses among Sb $_{2}$ S $_{3}$ phase shifters in the NIR range.

14 pages, 14 figures, 3 tables

Low-loss Sb2​S3​ Optical Phase Shifter Enabled by Optimizing Sputtering Conditions

Abstract

Low-loss Sb $_{2}$ S $_{3}$ Optical Phase Shifter Enabled by Optimizing Sputtering Conditions