Investigation of the confinement of high energy non-neutral proton beam in a bent magnetic mirror

By using the Particle-In-Cell(PIC) simulation method, we study how the proton beam is confined in a bent magnetic mirror. It is found that the loss rate of the charged particles in a bent mirror is less than that in the axi-symmetric mirror. For a special bent mirror with the deflection angle of the coils $\alpha=45^{\circ}$, it is found that the loss rate reaches maximum value at certain ion number density where the ion electrostatic oscillation frequency is equal to the ion cyclotron frequency. In addition, the loss rate is irrelevant to the direction of the proton beam. Our results may be helpful to devise a mirror. In order to obtain the least loss rate, we may choose a appropriate deflection angle, and have to avoid a certain ion number density at which the ion electrostatic oscillation frequency is equal to the ion cyclotron frequency.

Computational Design of a Magnetic Mirror

A computer-aided design (CAD) has been carried out to investigate the properties of the magnetic electron mirror design. The work has been focused on suggesting a mathematical formula to represent the radial displacement. The function that has been taken into consideration was suggested to give rise to the mirror action. A numerical solution is carried out for solving the Paraxial-ray equation for determining the optical properties such as the focal length, the spherical and chromatic aberration coefficients and the excitation of the mirror. The pole shape of the mirror has been determined in two dimensions. In the present work, the profile of the mirror determined from the suggested trajectory is the single-pole types. The coefficients of the chromatic and spherical aberrations of the magnetic mirror are determined and normalized in terms of the focal length. The operational requirements are determining the choice of the mirror.

Condensate Formation in Collisionless Plasma

Particle condensates in general magnetic mirror geometries in high-temperature plasmas may be caused by a discrete resonance with thermal ion-acoustic background noise near mirror points. The resonance breaks the bounce symmetry, temporally locking the particles to the resonant wavelength. The relevant correlation lengths are the Debye length in the parallel direction and the ion gyroradius in the perpendicular direction.

Cooperative optical wavefront engineering with atomic arrays

Natural materials typically interact weakly with the magnetic component of light which greatly limits their applications. This has led to the development of artificial metamaterials and metasurfaces. However, natural atoms, where only electric dipole transitions are relevant at optical frequencies, can cooperatively respond to light to form collective excitations with strong magnetic, as well as electric, interactions together with corresponding electric and magnetic mirror reflection properties. By combining the electric and magnetic collective degrees of freedom, we show that ultrathin planar arrays of atoms can be utilized as atomic lenses to focus light to subwavelength spots at the diffraction limit, to steer light at different angles allowing for optical sorting, and as converters between different angular momentum states. The method is based on coherently superposing induced electric and magnetic dipoles to engineer a quantum nanophotonic Huygens’ surface of atoms, giving full 2π phase control over the transmission, with close to zero reflection.