A different approach to construct dispersive mirrors （DMs） for ultrafast applications is proposed based on the high reflectivity and constant phase property of a novel metal in ultrawide spectral band. A 200- nm bandwidth DM, a high dispersive DM, and a complementary DM are designed with mixed metal multilayer dielectric stacks. The results show that the mixed-metal multilayer dielectric DMs （MMDMs） have much less layers and total thickness compared with an all-dielectric DM under the case of comparable performance. Such an approach will save manufacturing time and remarkably improve the stress of the DM.
Optical vortices are shown to be generated in the near-field of a slab lens with a realistic thin metal film due to the amplification of the evanescent wave by the metal film in the TM polarization.The vortices are connected to two saddle points near the output interface of the lens.By means of varying the position of the object with respect to the lens and the wavelength,the strength of circulation of the power flow,the position and the rotation of the vortices can be well controlled.The influence of the gain to the optical vortices is also illustrated.
