Fig. 5. Left column: Fy and F: force density plots for the p-polarized beam of Fig 4(a). Right olumn: Fy and F: force fields for the s-polarized beam of Fig 4(b). The free-space/dielectric interface is not shown to exclude from the color scale the region of high force density due to the induced surface charges in In our simulations the initial H-field amplitude was H.=2.6544 A/m, leading to an initial E-field amplitude(at the center of the Gaussian)Eo=ZHo=1000 V/m; here Zo=vuo, is the impedance of free-space. Ignoring for the moment the complication that the E-field consists of both Ey and Ez, the :-component of the beams Poynting vector is approximated as (10) The incident beams integrated power(per unit length along the x-axis)is then found to be ∫s(y,z=0.5um)dx=π8EJ5y2=0.5×10-3Wm (11) 三三s Fig. 6. Left to right: time-snapshot plots of Hx Ey E: components of a p-polarized,one- eam(o=0.65 um, FWHM=0.5 um), propagating in free-space in the gative =direction; the beams waist is at ==0.5 um #6863·$1500US Received 14 January 2005; revised 15 March 2005; accepted 15 March 2005 (C)2005OSA 4 April 2005/VoL 13, No. 7/OPTICS EXPRESS 2328Fig. 5. Left column: Fy and Fz force density plots for the p-polarized beam of Fig. 4(a). Right column: Fy and Fz force fields for the s-polarized beam of Fig. 4(b). The free-space/dielectric interface is not shown to exclude from the color scale the region of high force density due to the induced surface charges in the case of p-polarization. In our simulations the initial H-field amplitude was Ho = 2.6544 A/m, leading to an initial E-field amplitude (at the center of the Gaussian) Eo = ZoHo = 1000 V/m; here Zo = √µo/εo is the impedance of free-space. Ignoring for the moment the complication that the E-field consists of both Ey and Ez, the z-component of the beam’s Poynting vector is approximated as Sz( y, z = 0.5µm) = ½EoHo exp[−2(y/yo) 2 ]. (10) The incident beam’s integrated power (per unit length along the x-axis) is then found to be ∫ Sz( y, z = 0.5µm)dx = √π/8 EoHo yo = 0.5 × 10−3 W/m. (11) Fig. 6. Left to right: time-snapshot plots of Hx, Ey, Ez components of a p-polarized, one￾dimensional Gaussian beam (λo = 0.65 µm, FWHM = 0.5 µm), propagating in free-space in the negative z-direction; the beam’s waist is at z = 0.5 µm. (C) 2005 OSA 4 April 2005 / Vol. 13, No. 7 / OPTICS EXPRESS 2328 #6863 - $15.00 US Received 14 January 2005; revised 15 March 2005; accepted 15 March 2005