Abstract: An optical isolator on a silicon photonic integrated circuit. The optical isolator comprising: a polarization splitter; a polarization rotator; and a Faraday rotator. The Faraday rotator comprises: one or more magnets providing a magnetic field; and a silicon spiral delay line. The silicon spiral delay line being formed from a silicon waveguide shaped into a spiral region having no built-in phase shifters and a central region within the spiral region. The central region having no more than a total of 180 degree of phase shifters.

Abstract: Embodiments of the present invention provide improved livestock foot bath solutions that are capable of maintaining a low pH during longer periods of use in order to help prevent the metal salts from precipitating out of the solution and rendering the solution ineffective. Embodiments of the present invention provide improved livestock foot bath solutions that include one or more weak organic acids, such as polyprotic organic acids, in the aqueous solution, along with the dissolved metal salts. Embodiments of the invention may also include sulfuric acid, or some other strong acid, together with citric acid and the dissolved metal salts in the aqueous solution.

Abstract: An optical isolator on a silicon photonic integrated circuit. The optical isolator comprising: a polarization splitter; a polarization rotator; and a Faraday rotator. The Faraday rotator comprises: one or more magnets providing a magnetic field; and a silicon spiral delay line. The silicon spiral delay line being formed from a silicon waveguide shaped into a spiral region having no built-in phase shifters and a central region within the spiral region. The central region having no more than a total of 180 degree of phase shifters.