“…Besides sensing, FR is used for Faraday isolators and a lot of work has been done on increasing total FR. Gigantic FR has been reported for thin films [ 187 , 188 , 189 , 190 ], magneto-optical photonic crystals [ 20 , 191 , 192 , 193 ] and ferrofluids [ 22 , 194 , 195 , 196 , 197 ]. A few exotic structures possessing or mimicing FR have been reported [ 198 , 199 , 200 , 201 , 202 , 203 , 204 , 205 , 206 , 207 , 208 , 209 ].…”