Generalized optical theorem for propagation invariant beams

An analytical approximation to measure the extinction cross-section using: Localized Waves

“…This method can suit to study experimentally new structured beams, such as carving beams recently reported [48]. (12). Bottom: the Gaussian beam equation (13) using n = 3.…”

“…In the last few years, many interesting problems using beam shape methods related to optical manipulation and applications of the Lorenz-Mie theory [7,8], and several interesting papers have been published to generalize the optical theorem in electromagnetic theory and acoustic [9][10][11][12][13][14][15][16][17][18][19][20][21], in quantum mechanics [22], seismologic waves [23]. Also, recently the vector extinction effect in the OT using radially polarized cylindrical beams [24].…”

“…Figure1. Upper: the sinc beam given by equation(12). Bottom: the Gaussian beam equation (13) using n = 3.…”

Orbital angular momentum due to modes interference

“…Substituting expressions (1a) and (1b) for the electromagnetic fields into (11), a generalized expression for the Poynting vector of any invariant beam is obtained [29], (12) where (13) is the transversal electric part, (14) is the transversal magnetic part, and the interference modes TE/TM (15) The time averaged Poynting vector is independent of the z coordinate and it satisfies as was proven in [48]. It is important to remark that the interference term in the Poynting vector, expressed in Eq.…”

“…Recently, the scalar representation has been used to describe scattering problems using partial waves series in the far field approximation, where the impinging source is a structured field [9][10][11][12]. Effects also considering the polarization [13], the extinction [14] and driven acoustic radiation forces [15] have also been considered. Furthermore, the scalar approach is a natural representation for the structured beams family, also known as "non-diffracting beams".…”