The electro optic effect is the phenomenon that the refractive index of a material can be modified with an electric field. A novel technique enables the verdet constant to be easily measured. Densityfunctional theory calculations on the magneto. That branch of physics which deals with the influence of a magnetic field on optical phenomena. Measurement of magnetooptic kerr effect using piezobirefringent modulator j. The source of this optical anisotropy is the magnetisation m within surface domains which can be influenced by external forces such as magnetic fields. Electrooptic effect and elastooptic effect in this kind of fiber gratings are theoretically analyzed for the first time. Control light with heat and magnets magnetooptical kerr effect. A magnetooptic effect is any one of a number of phenomena in which an electromagnetic wave propagates through a medium that has been altered by the presence of a quasistatic magnetic field. Faraday effect, as well as to both classical and quantum theory of matter including the motions of electron. There is currently great interest in the magnetic and magnetooptical. Magnetooptic effect definition of magnetooptic effect by. It is shown that the effect polar magnetooptic effect is two order stronger than the equatorial. This seminar discusses magneto optic effects, phenomena in which optical properties of a medium and therefore its interaction with light are dependent on a magnetic field.
Reflection and absorption mode devices using magneto optic effects seem to be too small to be of interest. The program was a parallel effort on gaas and gap electro optic crystals. In physics the magnetooptic kerr effect moke or the surface magnetooptic kerr effect smoke is one of the magnetooptic effects. This chapter will discuss the theory and applications of the photomagnetic and magnetoptic effects. Longitudinal magnetooptic kerr effect system microsense. The linearly polarized wave can be seen as a superposition of the two above mentioned circularly polarized components, lcp and rcp. Electrooptic modulator based on machzehnder interferometer electrooptic effect, n 2 changes with e field, n 2 n 1. Magnetooptical devices the optics encyclopedia castera. Development of a surface magneto optic kerr effect magnetometer susan stoffer sorensen a senior thesis submitted to the faculty of brigham young university in partial fulfillment of the requirements for the degree of bachelor of science dr. European school on magnetism september 918, 2007 clujnapoca, romania. Theoretical study of electrooptic effect and elastooptic. The optic axis of this induced optical activity is aligned with the axis of the applied magnetic field. An electro optic effect is a change in the optical properties of a material in response to an electric field that varies slowly compared with the frequency of light.
A surprisingly large magnetooptical response occurs when mobile electrons in a cooled material become trapped by their interaction with the surrounding lattice. Karine chesnel, advisor department of physics and astronomy brigham young university december 20. Magneto optical kerr e ect moke photonphoton spectroscopies absorption ii. The program was a parallel effort on gaas and gap electrooptic crystals. When light is transmitted through a layer of magneto optic material, the result is called the faraday effect. Konstantinov petersburg nuclear physics institute, gatchina, russia 188350. Acoustooptical effects principles and applications. Some practical applications of the faraday magnetooptic. Magnetooptic effect article about magnetooptic effect. The physical origin of the magnetooptical effects is phenomenologically discussed. Magnetooptics article about magnetooptics by the free. Control light with heat and magnets magnetooptical kerr. Pdf faraday effect and other magnetooptic effects in. The strong thermo optic effect in silicon has been exploited for the fabrication of new sensing and communication devices.
Magnetooptic effect synonyms, magnetooptic effect pronunciation, magnetooptic effect translation, english dictionary definition of magnetooptic effect. It is desired to adapt the surface magneto optic kerr effect setup to an existing vacuum system already containing a vaporizer, mass spectrometers, leed, and a stm. Magnetooptic kerr effect sensors for fiber optic applications. Rp photonics encyclopedia electrooptic effect, pockels.
Magnetooptical kerr e ect moke photonphoton spectroscopies absorption ii. Finally the concept of magneto optic kerr effect is discussed and a setup utilizing the effect for magnetic probing is presented. The effect was first identified in 1842 by james joule when observing a sample of nickel. It is desired to adapt the surface magnetooptic kerr effect setup to an existing vacuum system already containing a vaporizer, mass spectrometers, leed, and a stm. Study of birefringence and electrooptic effect in sbn60 thin film. As with optics, acoustics has a history of similar duration, again starting with the ancient greeks. First, we will explain the theoretical background of magneto optic effects from both macroscopic and microscopic points of view. Giant electrooptic effect using polarizable dark states. Aug 10, 2015 learn how magneto optical storage discs work, and see how a focused laser can directly alter a materials optical characteristics.
This was then confirmed with experimentation in 1932 by debye and sears, and also by lucas and biquard. The electrooptic effect is the phenomenon that the refractive index of a material can be modified with an. An electrooptic effect is a change in the optical properties of a material in response to an electric field that varies slowly compared with the frequency of light. Faraday effect and other magnetooptic effects in semiconductors. Cotton mouton effect birefringence effect signal proportional to m. Then, some representatives of magnetooptical materials of transmission faraday effect and reflection kerr types are described. Magneto optic effect is a phenomenon in which an electromagnetic wave propagates through a medium and gets affected by the presence of a quasistatic magnetic field. Magnetooptic mo effects in magnetic multilayers with periodically stratified regions are analyzed for the case of normal light wave incidence and polar magnetization faraday and polar kerr effects. Development of a surface magnetooptic kerr effect magnetometer susan stoffer sorensen a senior thesis submitted to the faculty of brigham young university in partial fulfillment of the requirements for the degree of bachelor of science dr.
The photomagnetic and magnetooptic effects springerlink. The results of reflection from a magneto optic material are known as the magneto optic kerr effect not to be confused with the nonlinear kerr effect. The most significant of these properties are that the linear magnetooptic effect can produce circular birefringence and that, unlike other optical effects in dielectric media, it is nonreciprocal. The magneto optic effects and electro optic effects are the essential optic effects, although their theoretical explanations are not unified in the classical electromagnetic theory. An electrooptic effect is a change in the optical properties of a material in response to an. This has the effect that the optical rotation of the plane of polarization is only observed for rays travelling quite close to the optic axis. R r ss r sp r ps r pp re ection matrix is the only quantity accessible for sample investigations by optical means. An introduction to acoustooptics scott e pollack physics 7810 fundamentals of optics and lasers university of colorado, boulder december, 2002 abstract this paper is a brief introduction to acoustooptic phenomena. The existence of an interaction between light and sound was discovered by brillouin in the. A magnetooptic effect is any one of a number of phenomena in which an electromagnetic. Verdet constant describes the strength of faraday effect for a particular material. Kerr electro optic effect, in physics, the inducement of double refraction of light in a transparent substance when a strong electric field is applied in a direction transverse to the beam of light.
A novel sensor technique using a magnetic thin film as the sensing element and the magneto. The most significant of these properties are that the linear magneto optic effect can produce circular birefringence and. Detailed studies have been made of the magnetooptic effect in singlemode fibres exhibiting both linear and circular retardations. Electrooptic effect, n changes with e field, n n 1. The term encompasses a number of distinct phenomena, which can be subdivided into a change of the absorption. Magneto optical effects in magnetic materials arise due to the optical anisotropy of the materials.
The electrooptic effect is the phenomenon that the refractive index of a material can be modified with an electric field. Detailed studies have been made of the magneto optic effect in singlemode fibres exhibiting both linear and circular retardations. The research activities on the phenomenon of magneto optic effects has recently promulgated due to its versatile use in magneto optic recordings for high density magnetic data storage, magnetic field sensors and its applications in magnetoelectronics. The faraday and kerr effects zoe little, klaudia kozek, and. Propagation of weak optic signals in strong quasistatic fields description using renormalized linear parameters. Magnitude and nature of the quadratic electro optic effect in. In such a material, which is also called gyrotropic or gyromagnetic, left and rightrotating elliptical polarizations can propagate at different speeds, leading to a. The objective of this work was to measure the verdet constant for different transparent materials. We present to the reader the mathematical formalism used to describe this phenomena as well as the common. Magneto optical kerr e ect moke optics of multilayers i total optical response of multilayer described by re ection matrix.
In contrast, the acoustooptic effect has had a relatively short history, beginning with brillouin predicting the diffraction of light by an acoustic wave, being propagated. Longitudinal magnetooptic kerr effect system kerrmapper s300 and v300. Learn how magnetooptical storage discs work, and see how a focused laser can directly alter a materials optical characteristics. Reis focus center and department of physics, university. Some practical applications of the faraday magnetooptic effect, the kerr electrooptic effect, and the pockels electrooptic effect in the early decades of the 20th century. Nonlinear magnetooptic effects with ultranarrow widths. Recent advances towards electrooptic eo modulators make use of the pockels effect in noncentrosymmetric crystals which allows the. Development of a surface magnetooptic kerr effect magnetometer. It used the improved faraday effect at low fields to produce polarization. The research activities on the phenomenon of magnetooptic effects has recently promulgated due to its versatile use in magnetooptic recordings for high density magnetic data storage, magnetic field sensors and its applications in magnetoelectronics.
Magneto optic materials have unique physical properties that offer the opportunity of constructing devices with many special functions not possible from other photonic devices. Two new types of electrooptic effect that are linear in the applied electric field strength are theoretically predicted to exist in. A magnetic field, like any vector field, singles out a specific direction in space. Optics has had a very long and full history, from ancient greece, through the renaissance and modern times. The discovery of magneto optical effects evoked a new thought that the nature of light was an electromagnetic entity, and played a central role. Di erent energy ranges probes di erent part of the electronic structure of the matter. Electro optic effect and elasto optic effect in this kind of fiber gratings are theoretically analyzed for the first time. The kerrmapper family of tools utilizes the longitudinal magnetooptical kerr effect moke to characterize the magnetic properties of magnetic multilayer wafers for data storage, mram, and other magnetic sensors. Osa magnetooptic polar kerr and faraday effects in. The moct measures the electric current by means of faraday effect. In such a medium, which is also called gyrotropic or gyromagnetic, left and rightrotating elliptical polarizations can propagate at different speeds, leading to a number of important phenomena. Here we propose and demonstrate a giant electrooptic effect based on polarizable dark states. A temperature sensor, an electromagnetic energy sensor and an optical modulator are in particular presented. This effect can cause losses due to frictional heating.
Though both alloys have very similar electronic band structures, the moke spectra exhibit quite different features. Magnetooptic effects in singlemode fibres eprints soton. It is used in materials science research in devices such as the kerr microscope, to investigate the magnetization structure of materials. In double refraction, the index of refraction a measure of the amount the ray is bent on entering. Magneto optic current transducer consist of a sensor head located near the current carrying conductor, an electronic signal processing unit and fiber optical cables linking to these two parts. In physics the magneto optic kerr effect moke or the surface magneto optic kerr effect smoke is one of the magneto optic effects. Lbnl42066 preprint 102998 1 nonlinear magnetooptic effects with ultranarrow widths dmitry budker a,b, valeriy yashchuk a,c, and max zolotorev b a department of physics, university of california, berkeley, california 947207300 b e. Magnetooptics a branch of physics that studies changes in the optical properties of media upon exposure to a magnetic field and the peculiarities of the interaction of optical radiation light with matter placed in the field that are responsible for the changes. All practical magnetooptic devices exploit one or both of these two properties. These two phenomena are conceptually very similar but differ mainly from their point of reference. Applications of the effect, together with the magnitude of electromagnetic interference in optical fibres likely to be encountered in practice, are discussed. Conventional current transformers becomes more and more bulky and costly. The source of this optical anisotropy is the magnetisation m within surface domains which can be influenced.
The theory of the linear electro optic effect in crystals such as zincblende zns, gaas and gap is described by sterzer, blattner, and miniter reference 2. A novel sensor technique using a magnetic thin film as the sensing element and the magneto optic kerr effect as the optical read technique has been tested experimentally through magnetic field measurements. A chirped fiber grating with cladding made of uniaxial crystal material whose optical axis is parallel to the axis of grating, i. A pictorial representation of magneto optic effect. One of the main challenges of using silicon as an active photonic material is its low electrooptic coefficient. The faraday and kerr effects associated with a transition between the ground state and excited state. The theory of the linear electrooptic effect in crystals such as zincblende zns, gaas and gap is. The discovery of magnetooptical effects evoked a new thought that the nature of light was an electromagnetic entity, and played a central role.
Linear electrooptic effects due to high order spatial dispersion. Both magnetic circularlinear birefringence and dichroism, and void and cottonmouton effects are discussed. The electrooptic effect is the modification of the refractive index by an externally applied electrostatic field. In a magneto optic material the situation is a bit different. In addition, some work was done to grow ktn crystals, but the results as yet are inconclusive. Lawrence berkeley national laboratory, berkeley, california 94720 c b.
Thermooptic effect exploitation in silicon microstructures. Magnetooptic effect definition of magnetooptic effect. Acoustooptics is a phenomenon which deals with the interaction of light optics and sound acoustics. Finally the concept of magnetooptic kerr effect is discussed and a setup utilizing the effect for magnetic probing is presented. The research activities on the phenomenon of magneto optic effects has recently promulgated due to its versatile use in magneto optic recordings for high density magnetic data storage, magnetic field sensors and its applications in magneto electronics. Some practical applications of the faraday magneto optic effect, the kerr electro optic effect, and the pockels electro optic effect in the early decades of the 20th century. In the linear electrooptic effect, the size of the perturbation to the refractive index is directly proportional to the strength of the. Leo kristjansson, april 2017 research on very rapid processes let a beam of ordinary light pass through a polarizing nicol prism and a glass vessel. The strong thermooptic effect in silicon has been exploited for the fabrication of new sensing and communication devices.
Magnetism, light and the magneto optic kerr effect youtube. The term encompasses a number of distinct phenomena, which can be subdivided into. Magnetism, light and the magneto optic kerr effect joseph copland. The magnetooptic effects and electrooptic effects are the essential optic effects, although their theoretical explanations are not unified in the classical electromagnetic theory. Kerr electrooptic effect, in physics, the inducement of double refraction of light in a transparent substance when a strong electric field is applied in a direction transverse to the beam of light. Magnetooptic kerr effect is a property of light where light is reflected off a strongly.
In a magnetooptic material the situation is a bit different. Fundamental optical and magnetooptical constants of copt and. Magneto optic effect synonyms, magneto optic effect pronunciation, magneto optic effect translation, english dictionary definition of magneto optic effect. Magnetooptic effect article about magnetooptic effect by. The dependence of the refractive index on the applied electric field takes one of two forms.
To scramble and unscramble transmitted messages, an optical communication system was designed and effectively tested. This chapter will discuss the theory and applications of the photomagnetic and magnet optic effects. The electrooptic effect manifests itself as a change in the refractive index of a medium to which a static or a low frequency electric field is applied. It describes the changes to light reflected from a magnetized surface.
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