, Volume 5, Issue 1, pp 45–49

A Novel Design Method of Focusing-control Device by Modulating SPPs Scattering


DOI: 10.1007/s11468-009-9113-3

Cite this article as:
Hao, F., Wang, R. & Wang, J. Plasmonics (2010) 5: 45. doi:10.1007/s11468-009-9113-3


A novel design method of focusing device with a desired focal length is proposed, which consists of a nanometal slit surrounded with the grooves with fixed width and depth. By numerical calculation and analytic derivation, a relation between the phases of the light scattering from slit and grooves and the groove positions is revealed. Under the linear approximation, a design formula of focusing device is deduced, from which the position parameters of the grooves can be easily obtained to modulate the phase of the scattering light. The transmitted field distribution through the illustrative structures designed according to the proposed method is simulated with finite-difference time-domain (FDTD) method. The results show a good agreement with the theoretical analysis, and that the focal length can be controlled in several micrometers distance away from the metal exit surface, which verifies the feasibility of the method to deign focus-controlled optical elements in wavelength scale in integrated optics.


Surface plasmon polaritonsSubwavelength apertureScattering lightTransmission

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of PhysicsTsinghua UniversityBeijingPeople’s Republic of China
  2. 2.State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision InstrumentsTsinghua UniversityBeijingPeople’s Republic of China