A new method derived from the Z-scan by M.Sheik-baJiae et al.was employed to measure the thermooptic coefficient of materials effectively.A simple rule to determine the sign and magnitude of thermooptic coefficient an...A new method derived from the Z-scan by M.Sheik-baJiae et al.was employed to measure the thermooptic coefficient of materials effectively.A simple rule to determine the sign and magnitude of thermooptic coefficient and laser beam waist radius was obtained.展开更多
In this report,a modified‘position dispersion’method,in which the detecting aperture in the far-field is replaced by a circular board,is given to enhance the measurement sensitivity of nonlinear index,while keeps th...In this report,a modified‘position dispersion’method,in which the detecting aperture in the far-field is replaced by a circular board,is given to enhance the measurement sensitivity of nonlinear index,while keeps the simplicity.An increase of 5 times in sensitivity is obtained in our experiment,in which we employed a solution to produce the thermally induced nonlinearity.展开更多
A theoretical analysis of passive mode-locking in a thermal-stable ring cavity containing a Kerr medium and an aperture is presented.The analysis employing the beam propagation theory shows that the power dependence o...A theoretical analysis of passive mode-locking in a thermal-stable ring cavity containing a Kerr medium and an aperture is presented.The analysis employing the beam propagation theory shows that the power dependence of the cavity loss is extremely sensitive to the relative location of the Kerr medium and the aperture,and is different for the counterpropagating modes,so the unidirectional operation is expected.The combination of Kerr medium with an aperture acts as a p sition feedback,which is similar to the effect of a saturable absorber.展开更多
Graphene,a two-dimensional carbon atom sheet,has attracted tremendous attention and research interest because of its exceptional physical properties.Graphene has high mobility and optical transparency,in addition to f...Graphene,a two-dimensional carbon atom sheet,has attracted tremendous attention and research interest because of its exceptional physical properties.Graphene has high mobility and optical transparency,in addition to flexibility,robustness and environmental stability.The main focus so far has been on fundamental physics and electronic devices.However,because the linear dispersion of the Dirac electrons enables ultrawideband tunability,we believe its true potential lies in photonics and optoelectronics.In this review,we introduce recent advances in the nonlinear optical properties of graphene-based materials.The rise of graphene in nonlinear optics is shown by several recent results,ranging from saturable absorbers and the four-wave mixing effect to giant two-photon absorption,reverse saturable absorption and optical limiting.The relevant forms of the graphene-based materials include pure graphene,graphene oxide and graphene hybrids.展开更多
文摘A new method derived from the Z-scan by M.Sheik-baJiae et al.was employed to measure the thermooptic coefficient of materials effectively.A simple rule to determine the sign and magnitude of thermooptic coefficient and laser beam waist radius was obtained.
文摘In this report,a modified‘position dispersion’method,in which the detecting aperture in the far-field is replaced by a circular board,is given to enhance the measurement sensitivity of nonlinear index,while keeps the simplicity.An increase of 5 times in sensitivity is obtained in our experiment,in which we employed a solution to produce the thermally induced nonlinearity.
文摘A theoretical analysis of passive mode-locking in a thermal-stable ring cavity containing a Kerr medium and an aperture is presented.The analysis employing the beam propagation theory shows that the power dependence of the cavity loss is extremely sensitive to the relative location of the Kerr medium and the aperture,and is different for the counterpropagating modes,so the unidirectional operation is expected.The combination of Kerr medium with an aperture acts as a p sition feedback,which is similar to the effect of a saturable absorber.
基金supported by the National Basic Research Program of China(2011CB922003)the National Natural Science Foundation of China(10974103and11174159)+2 种基金the Program for New Century Excellent Talents in Universities(NCET-09-0484)the Natural Science Foundation of Tianjin(09JCYBJC04300)the Key Project of the Chinese Ministry of Education(109039)
文摘Graphene,a two-dimensional carbon atom sheet,has attracted tremendous attention and research interest because of its exceptional physical properties.Graphene has high mobility and optical transparency,in addition to flexibility,robustness and environmental stability.The main focus so far has been on fundamental physics and electronic devices.However,because the linear dispersion of the Dirac electrons enables ultrawideband tunability,we believe its true potential lies in photonics and optoelectronics.In this review,we introduce recent advances in the nonlinear optical properties of graphene-based materials.The rise of graphene in nonlinear optics is shown by several recent results,ranging from saturable absorbers and the four-wave mixing effect to giant two-photon absorption,reverse saturable absorption and optical limiting.The relevant forms of the graphene-based materials include pure graphene,graphene oxide and graphene hybrids.