Sensitive magnetic field sensor using 2D magnetic photonic crystal slab waveguide based on BIG/GGG structure

A kind of magnetic field sensor (MFS) using a two-dimensional (2D) magnetic photonic crystal (MPC) slab waveguide as the sensing structure is proposed and investigated numerically. The slab structure is based on bismuth iron garnet (BIG), a well-known magnetic material with effective magnetooptical (MO) properties, sandwiched with gadolinium gallium garnet (GGG) as substrate. The complete photonic bandgap (PBG) of the 2D MPC is simulated and optimized for realization of polarization-independent waveguides. The simulation results show that the width and position of the complete PBG depend on the thickness of the BIG slab and the radius of the air holes used in the design. By reducing the lightwave propagation losses and enhancing the mode conversion ratio, increased sensitivity is obtained. Based on the Faraday effect, a good linear relationship is observed between the normalized output light intensity and the magnetic field strength as the gyrotropy parameter g is varied from 0.13 to 0.19, a g-range used as the sensor dynamic range. The remarkable enhancement in sensing performance due to the MO effect makes the designed device suitable for magnetic field sensing. The results are discussed to provide a basis for investigation of 2D MPC slab waveguides based on the same structure, which are of particular interest for development of highly sensitive MFSs.     

The Effects of Annealing After Equal Channel Angular Extrusion (ECAE) on Mechanical and Magnetic Properties of 49Fe-49Co-2V Alloy

Metallurgical and Materials Transactions A - Equal channel angular extrusion (ECAE) of 49Fe-49Co-2V, also known as Hiperco® 50A or Permendur-2V, greatly improves the strength and ductility of...     

PLACE,COUNTRY, CHOROGRAPHY: Towards a Kinesthetic and Narrative Practice of Place

Mainstream practices of place are founded on visual notions of landscape, conveyed through Picturesque engagement with the environment. By contrast. Indigenous experiences of place concern country, not landscape. They are not primarily specular forms of engagement. Rather, they are chorographic—in the sense that they relate to space and place; and choreographic—inthesense that space and place are elaborated kinesthetically through practices of walking and speaking stories associated with country. These kinds of experiences of place—where topography and the body are encountered and gathered through narrative recollection and enunciation—suggest implications for the way the environment is encountered and addressed in architectural design.     

The significance of the sword

Human aggression affects and is affected by the environment. The study of militaria can illuminate questions of social change and choice. Knowledge of history should modify behaviour.