TY - JOUR
T1 - Polarization insensitive linear intensity modulation in a Sagnac fiber-optic loop with an electro-optic cell and optoelectronic feedback
AU - Garcia-Weidner, A.
AU - Torres, C. Torres
AU - Khomenko, A. V.
AU - Garcia-Zarate, M. A.
PY - 2003
Y1 - 2003
N2 - We present a modulation scheme consisting of a fiber-optic Sagnac interferometer, which has an electro-optic modulator (Pockels cell) in the loop of the interferometer. In order to diminish the nonlinearity of the Sagnac interferometer transmittance function, we monitor a very small part of the output light intensity by means of a photodiode and then amplify this signal by a constant factor ξ. This amplified signal is added to the electrical modulating signal that is being applied to the electro-optical modulator. The consequence of introducing this feedback loop is that by properly choosing the amplifying factor ξ, we can increase the linearity of the modulation. The device is insensitive to the polarization state of the input light, so it should be used for intensity modulation of nonpolarized light with up to 100% modulation depth. The theoretical and experimental examination of the device is presented.
AB - We present a modulation scheme consisting of a fiber-optic Sagnac interferometer, which has an electro-optic modulator (Pockels cell) in the loop of the interferometer. In order to diminish the nonlinearity of the Sagnac interferometer transmittance function, we monitor a very small part of the output light intensity by means of a photodiode and then amplify this signal by a constant factor ξ. This amplified signal is added to the electrical modulating signal that is being applied to the electro-optical modulator. The consequence of introducing this feedback loop is that by properly choosing the amplifying factor ξ, we can increase the linearity of the modulation. The device is insensitive to the polarization state of the input light, so it should be used for intensity modulation of nonpolarized light with up to 100% modulation depth. The theoretical and experimental examination of the device is presented.
KW - Electro-optic modulators
KW - Optical fiber devices
KW - Sagnac interferometer
UR - http://www.scopus.com/inward/record.url?scp=0037402060&partnerID=8YFLogxK
U2 - 10.1016/S0143-8166(02)00046-5
DO - 10.1016/S0143-8166(02)00046-5
M3 - Artículo
AN - SCOPUS:0037402060
SN - 0143-8166
VL - 39
SP - 567
EP - 579
JO - Optics and Lasers in Engineering
JF - Optics and Lasers in Engineering
IS - 5-6
ER -