Optical and magnetic properties of a transparent garnet film for atomic physics experiments

• Published in: AIP advances Vol. 6; no. 12; pp. 125023 - 125023-7
• Main Authors: Saito, Mari, Tajima, Ryoichi, Kiyosawa, Ryota, Nagata, Yugo, Shimada, Hiroyuki, Ishibashi, Takayuki, Hatakeyama, Atsushi
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 01-12-2016; AIP Publishing LLC
• Subjects: Atomic physics; Evanescent waves; Faraday effect; Laser cooling; Magnetic domains; Magnetic mirrors; Magnetic properties; Magnetism; Optical communication; Optical properties; Thickness; Wavelengths
• ISSN: 2158-3226; 2158-3226
• DOI: 10.1063/1.4972125

We investigated the optical and magnetic properties of a transparent magnetic garnet with a particular focus on its applications to atomic physics experiments. The garnet film used in this study was a magnetically soft material that was originally designed for a Faraday rotator at optical communication wavelengths in the near infrared region. The film had a thickness of 2.1 μm and a small optical loss at a wavelength of
λ
=
780
nm resonant with Rb atoms. The Faraday effect was also small and, thus, barely affected the polarization of light at
λ
=
780
nm. In contrast, large Faraday rotation angles at shorter wavelengths enabled us to visualize magnetic domains, which were perpendicularly magnetized in alternate directions with a period of 3.6 μm. We confirmed the generation of an evanescent wave on the garnet film, which can be used for the optical observation and manipulation of atoms on the surface of the film. Finally, we demonstrated a magnetic mirror for laser-cooled Rb atoms using the garnet film.