Photomask / Direct Write Lithography Documents

Magnetization reversal processes of submicron NiO/Fe19Ni81 exchange-coupled Hall cross with a variable width in the range from 0.2 to 0.4 µm were studied by the magnetoresisitivity and the planar Hall effect measurements. The magnetization reversal was found to take place via a coherent rotation in the Hall cross, suggesting that the size of the antiferromagnetic domain is regulated by the wire width. The magnitude of the exchange coupling field Hex varied in proportion to the inverse wire width.

The magnetization reversal phenomenon in a submicron magnetic wire with a trilayer structure consisting of NiFe(200 Å)/Cu(100 Å)/NiFe(50 Å) was investigated by measuring the electric resistance in an external magnetic field. A giant magnetoresistance (GMR) effect of about 0.8% was observed when the magnetizations in two NiFe layers are oriented antiparallel. It is demonstrated that magnetization reversal phenomena  can be very sensitively investigated by utilizing the GMR effect.

The motion of a magnetic domain wall in a submicrometer magnetic wire was detected by use of the giant magnetoresistance effect. Magnetization reversal in a submicriometer magnetic wire takes place by the propagation of a magnetic domain wall, which can be treated as a "particle." The propagation velocity of the magnetic domain wall was determined as a function of the applied magnetic field.

Arrays of submicron polycrystalline and epitaxially grown (1 0 0) hep Co dots and anitdots were prepared in order to study the magnetization reversal processes influenced by well defined anisotropy, dipolar and exchange fields. The magnetization reversal processes for both polycrystalline and epitaxial Co dot arrays are found to be initiated by domain wall nucleation. The domain wall propagation is regulated by the evolution of the effective internal field. The antidots exhibit perculiar stripe domains in the remanent state. The direction of the stripes is well determined by the applied magnetic field direction.

Selected excerpts.

Metadevices based on dielectric nanostructured surfaces with both electric and magnetic Mie-type resonances have resulted in the best efficiency to date for functional flat optics with only one disadvantage: a narrow operational bandwidth. Here we experimentally demonstrate broadband transparent all-dielectric metasurfaces for highly efficient polarization manipulation. We utilize the generalized Huygens principle, with a superposition of the scattering contributions from several electric and magnetic multipolar modes of the constituent meta-atoms, to achieve destructive interference in reflection over a large spectral bandwidth. By employing this novel concept, we demonstrate reflectionless (∼90% transmission) half-wave plates, quarter-wave plates, and vector beam q-plates that can operate across multiple telecom bands with ∼99% polarization conversion efficiency.