© 2026 Aqora Quantum S.A.S.

Terms Privacy Legal Notice

Electronics and Communications in Japan (Part II Electronics)

Theoretical analysis of optical bistability of a faraday medium

Masao Hirano

Published Jan 1, 1994• 0 citations

Abstract

Abstract An optical bistable device can be useful not only for optical memory but also for optical sensing by using its binary signal process characteristics. In this case, if a nonlinear Faraday medium is used in the optical bistable device, some interesting features can be obtained as already shown by the present author. Those unique characteristics are that, by controlling the polarization direction by an external magnetic field, a multiple interference can also be controlled not only by the phase associated with an optical path variation but also the polarization direction. This paper describes a theoretical analysis of the fluctuation of transmission and reflection as a function of an absorption in a medium besides the incident intensity reduction and discusses the bistability characteristics and the threshold values against the parameters. It is shown that the control of the bistable function, the realization of a low threshold value, and the increase of a discontinuous power variation ratio (= optical intensity ratio between on and off in the binary signal process) at the threshold value are accomplished as the result of the introduction of the external magnetic field control method. Therefore, it can be concluded that a Faraday medium is very useful for an optical bistable device.

DOI: 10.1002/ecjb.4420770104

Related papers

Theoretical analysis of the optical bistability with Faraday effect

Masao Hirano

We have proposed and discussed that an introduction of the Faraday medium to the optical bistable devices brings new and good characteristics on the application to optical sensing. In this paper, characteristics of the optical bistability are analyzed theoretically for the optical bistable operation with the Faraday effect, the threshold power, and several parameter dependences of the characteristic. Consequently, by controlling them with an external magnetic field which is an operatable factor, the optical bistability shows much usefulness and effectiveness by the following points: the controllability of the bistable operation, the reduction in the threshold power, and the enlargement in the discontinuous power variation ratio.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 25, 1993•1 citation

Optical bistability on a thin-film Faraday rotator

Masao Hirano

We proposed an all-optical bistable unit made of a Faraday medium and investigated theoretically its unique characteristics. Optical bistability in our proposed unit was experimantally confirmed. In this paper, using a 830 nm wavelength laser diode and a thin garnet film rotator as a Fabry-Perot resonator, optical bistability is confirmed again. Bistable characteristics, threshold incident power, on-off power ratio, and dynamic characteristics, are examined to attain controllability with the external magnetic field. In our proposed unit's construction, an all-optical sensing device (a magnetic field sensor) is proposed and evaluated for application to the OB operation.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 30, 1994•0 citations

Optical Bistability

Guang S. He

When the output parameter of an optical device could be a multivalued function of the input parameter, this device can be working in an optical bistable status. The most typical optical bistable device is a Fabry–Perot cavity containing a nonlinear optical medium, the refractive index of which depends on the light intensity. Upon the action of an intense input optical beam, the transmitted (or reflected) intensity of this device may exhibit a nonlinear response to the incident light intensity variation and, especially under appropriate working conditions, the characteristic output/input curve may manifest a single (or multiple) hysteresis loop(s). Such type of optical bistable device can be used as an optical differential amplifier, optical switch, optical limiter, optical clipper, optical discriminator, or an optical memory element, depending on the chosen nonlinear medium and operation conditions.

Oxford University Press eBooks•Oct 30, 2014•1 citation

Optical Bistable Operation in Fabry-Perot Resonator Constructed with Thin-Film Faraday Medium

Masao Hirano

This letter deals with observations and a study on optical bistability in a thin Fabry-Perot resonator made of a Faraday medium. Using a commercial TbBi-garnet film as the Fabry-Perot resonator, it was established experimentally that the resonator represents an optical bistability, by treating both the thermally induced nonlinear effect and the Faraday effect, and that its characteristics are controlled by an external magnetic field through the Faraday effect.

Japanese Journal of Applied Physics•Apr 1, 1994•1 citation

OPTICAL BISTABILITY IN A DEGENERATE TWO-LEVEL EIT MEDIUM UNDER THE INFLUENCE OF AN EXTERNAL MAGNETIC FIELD: AN ANALYTICAL APPROACH

Le Thi Minh Phuong, Dinh Xuan Khoa, Nguyen Huy Bang +4 more

We investigate the behavior of optical bistability in a degenerate two-level atomic medium using an external magnetic field to separate the lower level into two distinct levels that both connect to an upper level by the probe and coupling laser fields. Based on analytical solutions, the absorption spectrum and behavior of optical bistability in an electromagnetically induced transparency regime under an external magnetic field are investigated. By controlling the external magnetic field, we find that the appearance and disappearance of the optical bistability can be easily controlled according to the strength of the magnetic field in the transparent window domain. Furthermore, the effects of the intensity of the coupling laser field and the parameters of the system on the behavior of optical bistability are also considered. The proposed model is useful for applications in all-optical switches and magneto-optic storage devices.

Dalat University Journal of Science•Jul 22, 2021•1 citation

Low-threshold bistable reflection assisted by oscillating wave interaction with Kerr nonlinear medium*

Yingcong Zhang, Wenjuan Cai, Xianping Wang +5 more

Owing to the enormously enhanced oscillating wave, a minute variation of the incident light intensity will give rise to a change in the dielectric constant of the Kerr nonlinear medium and lead to a bistable reflection with an ultra-low threshold intensity, which is closely related to the angle of incidence and the thickness of the Kerr nonlinear medium. The criterion for the existence of optical bistability is derived. Our bistability scheme is simple and not limited to the TM-polarization.

Chinese Physics B•Jan 29, 2021•1 citation

Abstract An optical bistable device can be useful not only for optical memory but also for optical sensing by using its binary signal process characteristics. In this case, if a nonlinear Faraday medium is used in the optical bistable device, some interesting features can be obtained as already shown by the present author. Those unique characteristics are that, by controlling the polarization direction by an external magnetic field, a multiple interference can also be controlled not only by the phase associated with an optical path variation but also the polarization direction. This paper describes a theoretical analysis of the fluctuation of transmission and reflection as a function of an absorption in a medium besides the incident intensity reduction and discusses the bistability characteristics and the threshold values against the parameters. It is shown that the control of the bistable function, the realization of a low threshold value, and the increase of a discontinuous power variation ratio (= optical intensity ratio between on and off in the binary signal process) at the threshold value are accomplished as the result of the introduction of the external magnetic field control method. Therefore, it can be concluded that a Faraday medium is very useful for an optical bistable device.

We have proposed and discussed that an introduction of the Faraday medium to the optical bistable devices brings new and good characteristics on the application to optical sensing. In this paper, characteristics of the optical bistability are analyzed theoretically for the optical bistable operation with the Faraday effect, the threshold power, and several parameter dependences of the characteristic. Consequently, by controlling them with an external magnetic field which is an operatable factor, the optical bistability shows much usefulness and effectiveness by the following points: the controllability of the bistable operation, the reduction in the threshold power, and the enlargement in the discontinuous power variation ratio.

We proposed an all-optical bistable unit made of a Faraday medium and investigated theoretically its unique characteristics. Optical bistability in our proposed unit was experimantally confirmed. In this paper, using a 830 nm wavelength laser diode and a thin garnet film rotator as a Fabry-Perot resonator, optical bistability is confirmed again. Bistable characteristics, threshold incident power, on-off power ratio, and dynamic characteristics, are examined to attain controllability with the external magnetic field. In our proposed unit's construction, an all-optical sensing device (a magnetic field sensor) is proposed and evaluated for application to the OB operation.

When the output parameter of an optical device could be a multivalued function of the input parameter, this device can be working in an optical bistable status. The most typical optical bistable device is a Fabry–Perot cavity containing a nonlinear optical medium, the refractive index of which depends on the light intensity. Upon the action of an intense input optical beam, the transmitted (or reflected) intensity of this device may exhibit a nonlinear response to the incident light intensity variation and, especially under appropriate working conditions, the characteristic output/input curve may manifest a single (or multiple) hysteresis loop(s). Such type of optical bistable device can be used as an optical differential amplifier, optical switch, optical limiter, optical clipper, optical discriminator, or an optical memory element, depending on the chosen nonlinear medium and operation conditions.

We investigate the behavior of optical bistability in a degenerate two-level atomic medium using an external magnetic field to separate the lower level into two distinct levels that both connect to an upper level by the probe and coupling laser fields. Based on analytical solutions, the absorption spectrum and behavior of optical bistability in an electromagnetically induced transparency regime under an external magnetic field are investigated. By controlling the external magnetic field, we find that the appearance and disappearance of the optical bistability can be easily controlled according to the strength of the magnetic field in the transparent window domain. Furthermore, the effects of the intensity of the coupling laser field and the parameters of the system on the behavior of optical bistability are also considered. The proposed model is useful for applications in all-optical switches and magneto-optic storage devices.