Optical modulators using semiconductor nano-structures: Difference between revisions
wikademia>Jmk8755 No edit summary |
wikademia>Jmk8755 No edit summary |
||
| Line 26: | Line 26: | ||
=== Acousto-optic modulator === | |||
Acousto-optic modulators are used to vary and control laser beam intensity. A Bragg configuration gives a single first order output beam, whose intensity is directly linked to the power of RF control signal. The rise time of the modulator is simply deduced by the necessary time for the acoustic wave to travel through the laser beam. For highest speeds the laser beam will be focused down, forming a beam waist as it passes through the modulator. | Acousto-optic modulators are used to vary and control laser beam intensity. A Bragg configuration gives a single first order output beam, whose intensity is directly linked to the power of RF control signal. The rise time of the modulator is simply deduced by the necessary time for the acoustic wave to travel through the laser beam. For highest speeds the laser beam will be focused down, forming a beam waist as it passes through the modulator. | ||
| Line 33: | Line 33: | ||
=== Megneto-optic modulator === | |||
A dc magnetic field Hdc is applied perpendicular to the light propagation direction to produce a single domain, transverse directed 4~Ms. The rf modulation field Hrf, applied by means of a coil along the light propagation direction, wobbles 4~Ms through an angle of @ and produces a time varying magnetization component in the longitudinal direction. This component then produces an ac variation in the plane of polarization via the longitudinal Faraday effect. Conversion to [[amplitude modulation]] is accomplished by the indicated analyzer. | A dc magnetic field Hdc is applied perpendicular to the light propagation direction to produce a single domain, transverse directed 4~Ms. The rf modulation field Hrf, applied by means of a coil along the light propagation direction, wobbles 4~Ms through an angle of @ and produces a time varying magnetization component in the longitudinal direction. This component then produces an ac variation in the plane of polarization via the longitudinal Faraday effect. Conversion to [[amplitude modulation]] is accomplished by the indicated analyzer. | ||
| Line 47: | Line 47: | ||
=== Electro-optic modulator of nano-structures === | |||
Micrometre-scale silicon electro-optic modulator<ref>Nature 435, 325-327 (19 May 2005)</ref> | Micrometre-scale silicon electro-optic modulator<ref>Nature 435, 325-327 (19 May 2005)</ref> | ||
| Line 55: | Line 55: | ||
=== Acousto-optic modulator of nano-structures === | |||
Acoustic solitons in semiconductor nanostructures<ref>Journal of Physics: Conference Series 92 (PHONONS 2007)</ref> | Acoustic solitons in semiconductor nanostructures<ref>Journal of Physics: Conference Series 92 (PHONONS 2007)</ref> | ||
| Line 63: | Line 63: | ||
=== Magneto-optic modulator of nano-structures === | |||
Wideband magneto-optic modulation in a bismuth-substituted yttrium iron garnet waveguide<ref>Optics Communications Volume 220, Issues 4-6</ref> | Wideband magneto-optic modulation in a bismuth-substituted yttrium iron garnet waveguide<ref>Optics Communications Volume 220, Issues 4-6</ref> | ||
| Line 71: | Line 71: | ||
=== Other semiconductor nanostructures of optical modulator === | |||
MODULATION OF THz RADIATION BY SEMICONDUCTOR NANOSTRUCTURES<ref>MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 35, No. 5, December 5 2002</ref> | MODULATION OF THz RADIATION BY SEMICONDUCTOR NANOSTRUCTURES<ref>MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 35, No. 5, December 5 2002</ref> | ||
| Line 84: | Line 84: | ||
=== Electro-optic modulator === | |||
| Line 95: | Line 95: | ||
=== Acousto-optic modulator of nano-structures === | |||