An object or system is said to be chiral if it cannot be superimposed on its mirror reflection.Chirality is ubiquitous in nature,for example,in protein molecules and chiral phonons—acoustic waves carrying angular mom...An object or system is said to be chiral if it cannot be superimposed on its mirror reflection.Chirality is ubiquitous in nature,for example,in protein molecules and chiral phonons—acoustic waves carrying angular momentum—which are usually either intrinsically present or magnetically excited in suitable materials.Here,we report the use of intervortex forward Brillouin scattering to optically excite chiral flexural phonons in a twisted photonic crystal fiber,which is itself a chiral material capable of robustly preserving circularly polarized optical vortex states.The phonons induce a spatiotemporal rotating linear birefringence that acts back on the optical vortex modes,coupling them together.We demonstrate intervortex frequency conversion under the mediation of chiral flexural phonons and show that,for the same phonons,backward and forward intervortex conversion occurs at different wavelengths.The results open up,to our knowledge,new perspectives for Brillouin scattering and the chiral flexural phonons offer new opportunities for vortex-related information processing and multi-dimensional vectorial optical sensing.展开更多
Stimulated Brillouin scattering(SBS)has many applications;for example,in sensing,microwave photonics,and signal processing.Here,we report the first experimental study of SBS in chiral photonic crystal fiber(PCF),which...Stimulated Brillouin scattering(SBS)has many applications;for example,in sensing,microwave photonics,and signal processing.Here,we report the first experimental study of SBS in chiral photonic crystal fiber(PCF),which displays optical activity and robustly maintains circular polarization states against external perturbations.As a result,circularly polarized pump light is cleanly backscattered into a Stokes signal with the orthogonal circular polarization state,as is required by angular momentum conservation.By comparison,untwisted PCF generates a Stokes signal with an unpredictable polarization state,owing to its high sensitivity to external perturbations.We use chiral PCF to realize a circularly polarized continuous-wave Brillouin laser.The results pave the way for a new generation of stable circularly polarized SBS systems with applications in quantum manipulation,optical tweezers,optical gyroscopes,and fiber sensors.展开更多
文摘An object or system is said to be chiral if it cannot be superimposed on its mirror reflection.Chirality is ubiquitous in nature,for example,in protein molecules and chiral phonons—acoustic waves carrying angular momentum—which are usually either intrinsically present or magnetically excited in suitable materials.Here,we report the use of intervortex forward Brillouin scattering to optically excite chiral flexural phonons in a twisted photonic crystal fiber,which is itself a chiral material capable of robustly preserving circularly polarized optical vortex states.The phonons induce a spatiotemporal rotating linear birefringence that acts back on the optical vortex modes,coupling them together.We demonstrate intervortex frequency conversion under the mediation of chiral flexural phonons and show that,for the same phonons,backward and forward intervortex conversion occurs at different wavelengths.The results open up,to our knowledge,new perspectives for Brillouin scattering and the chiral flexural phonons offer new opportunities for vortex-related information processing and multi-dimensional vectorial optical sensing.
文摘Stimulated Brillouin scattering(SBS)has many applications;for example,in sensing,microwave photonics,and signal processing.Here,we report the first experimental study of SBS in chiral photonic crystal fiber(PCF),which displays optical activity and robustly maintains circular polarization states against external perturbations.As a result,circularly polarized pump light is cleanly backscattered into a Stokes signal with the orthogonal circular polarization state,as is required by angular momentum conservation.By comparison,untwisted PCF generates a Stokes signal with an unpredictable polarization state,owing to its high sensitivity to external perturbations.We use chiral PCF to realize a circularly polarized continuous-wave Brillouin laser.The results pave the way for a new generation of stable circularly polarized SBS systems with applications in quantum manipulation,optical tweezers,optical gyroscopes,and fiber sensors.
