We have found an alternative way of achieving a doughnutlike focused spot by simply melting a subwavelength scatterer in a polycarbonate/ZnS sample. The near-field microscopy technique is used to directly measure the induced doughnut spot in the near-field regime. A numerical model based on rigorous solution of the Maxwell’s equations is proposed to study the phenomena. The simulations help to understand the optical mechanism behind the spot formation.
© 2012 Optical Society of America
Original Manuscript: September 13, 2012
Manuscript Accepted: October 10, 2012
Published: October 30, 2012
Alberto da Costa Assafrao, Arthur J. H. Wachters, Silvania F. Pereira, and H. Paul Urbach, "Near-field self-induced hollow spot through localized heating of polycarbonate/ZnS stack layer," Appl. Opt. 51, 7684-7689 (2012)