Dynamically sculpturing plasmonic vortices: from integer to fractional orbital angular momentum
26
Citation
35
Reference
10
Related Paper
Citation Trend
Abstract:
Abstract As a fundamental tool for light-matter interactions, plasmonic vortex (PV) is extremely useful due to the unique near field property. However, it is a pity that, up to now, the orbital angular momentum (OAM) carried by PVs could not be dynamically and continuously tuned in practice as well as the properties of fractional PVs are still not well investigated. By comparing with two previously reported methods, it is suggested that our proposal of utilizing the propagation induced radial phase gradient of incident Laguerre-Gaussian (LG) beam is a promising candidate to sculpture PVs from integer to fractional OAM dynamically. Consequently, the preset OAM of PVs could have four composing parts: the incident spin and orbital angular momentum, the geometric contribution of chiral plasmonic structure, and the radial phase gradient dependent contribution. Moreover, an analytical expression for the fractional PV is derived as a linear superposition of infinite numbers of integer PVs described by Bessel function of the first kind. It is also shown that the actual mean OAM of a fractional PV would deviate from the preset value, which is similar with previous results for spatial fractional optical vortices.Keywords:
Optical vortex
Azimuthal quantum number
The realization that light beams can have quantized orbital angular momentum in addition to spin angular momentum has led, in recent years, to novel experiments in quantum mechanics and new methods for manipulating microparticles
Azimuthal quantum number
Orbital motion
Angular momentum operator
Cite
Citations (657)
We explain that, unlike the spin angular momentum of a light beam which is always intrinsic, the orbital angular momentum may be either extrinsic or intrinsic. Numerical calculations of both spin and orbital angular momentum are confirmed by means of experiments with particles trapped off axis in optical tweezers, where the size of the particle means it interacts with only a fraction of the beam profile. Orbital angular momentum is intrinsic only when the interaction with matter is about an axis where there is no net transverse momentum.
Orbital motion
Azimuthal quantum number
Angular momentum operator
Cite
Citations (947)
Like the eletron, the photon carries spin and orbital angular momentum caused by the polarization and the spatial phase distribution of light, respectively. Since the first observation of an optical vortex beam with orbital angular momentum (OAM), the use of an optical vortex beam has led to further studies on the light-matter interaction, the quantum nature of light, and a number of applications. In this article, using a metasurface with geometrical phase, we introduce the fundamental origins and some important applications of light with spin-orbit angular momentum as examples, including optical vortex tweezer and quantum entanglement of the spin-orbital angular momentum.
Orbital motion
Azimuthal quantum number
Optical vortex
Light beam
Cite
Citations (0)
Three pairs of abstract operators are presented which serve as ladder operators for the orbital angular momentum quantum numbers l and m. These operators are used to prove the restriction of l to integral values and also to obtain matrix elements for orbital angular momentum state vectors. The calculations are based entirely on an application of the abstract (Dirac) operator method to orbital angular momentum.
Azimuthal quantum number
Angular momentum operator
Operator (biology)
Orbital motion
Quantum number
Cite
Citations (5)
The properties of orbital angular momentum operators are examined within the framework of the formal theory of angular momentum. It is demonstrated that the occurrence of only integral quantum numbers in the orbital theory is a consequence of the particular form of the orbital operators. Single-valuedness of the eigenfunctions need not be postulated.
Azimuthal quantum number
Orbital motion
Angular momentum operator
Quantum number
Eigenfunction
Cite
Citations (13)
Angular momentum of the cylindrical vector beam has been investigated according to general definition of angular momentum of electromagnetic wave.It is shown that the spin angular momentum is mainly dependent on the polarization,but the orbital angular momentum are both dependent on the helical phase factor and the polarization,and the spin angular momentum and the orbital angular momentum of the non-paraxial beam are also related with the structure of the beam.It is also shown that the angular momentum could not be separated into the spin and orbital parts that are independent of each other in the case of paraxial approximation.
Azimuthal quantum number
Angular momentum operator
Orbital motion
Cite
Citations (0)
Jones matrices describe the polarization, or spin angular momentum, of a light beam as it passes through an optical system. We devise an equivalent of the Jones matrix formulation for light possessing orbital angular momentum. The matrices are then developed to account for light that has both spin and orbital angular momentum.
Azimuthal quantum number
Orbital motion
Angular momentum operator
Light beam
Hydrogen-like atom
Cite
Citations (68)
Vortex light beams are used to compact data channels because they have orbital angular moments with an infinite number of possible quantum states. This allows the transmission of optical information in a single physical medium by encoding the data by different optical vortices. The aim of the paper is to modeling and analysis the state of orbital angular momentum of laser beams during propagation through free space and parabolic fiber in the presence of random fluctuations of the optical medium. The modeling results for Laguerre-Gauss beams showed that after the beams distortion by random noise, they self-regenerate with further propagation in an undisturbed medium, and it is possible to determine the initial state of the orbital angular momentum of the beam by means of binarization of the field expansion coefficients in angular harmonics.
Optical vortex
Azimuthal quantum number
Orbital motion
Light beam
Quantum noise
Cite
Citations (0)
We propose the optical zero-spin-to-orbital angular momentum and linear-to-vector polarization conversion realization by an optically active plate with a topological charge. By the geometric phase, the zero spin will also contribute to the orbital optical angular momentum and induce the optical spin-to-orbital angular momentum conversion. Moreover, the proposed angular momentum converter can convert the polarization from linear to radial or azimuthal with high efficiency. We believe that the proposed efficient converter will find potential applications in the study of quantum information conversion, generation and interaction of vector fields, phase and polarization singularities, etc.
Azimuthal quantum number
Cite
Citations (8)
The expression for the total angular momentum carried by a laser optical vortex beam, splits, in the paraxial approximation, into two terms which seem to represent orbital and spin angular momentum respectively. There are, however, two very different competing versions of the formula for the spin angular momentum, one based on the use of the Poynting vector, as in classical electrodynamics, the other related to the canonical expression for the angular momentum which occurs in Quantum Electrodynamic. I analyze the possibility that a sufficiently sensitive optical measurement could decide which of these corresponds to the actual physical angular momentum carried by the beam.
Azimuthal quantum number
Angular momentum operator
Orbital motion
Optical vortex
Cite
Citations (12)