{"id":355783,"date":"2024-03-06T23:51:44","date_gmt":"2024-03-06T23:51:44","guid":{"rendered":"\/forum\/forums\/topic\/reflection-and-transmission-values-do-not-add-up-to-1\/"},"modified":"2024-03-06T23:51:44","modified_gmt":"2024-03-06T23:51:44","slug":"reflection-and-transmission-values-do-not-add-up-to-1","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/reflection-and-transmission-values-do-not-add-up-to-1\/","title":{"rendered":"Reflection and transmission values do not add up to 1"},"content":{"rendered":"

Hello, I am currently trying to simulate a 40nm thin film of Au using FDTD with a plane wave incidence at 1550nm, 0BW. <\/p>\n

After analyzing my results I have noticed that my reflection and transmission values are not making sense. I am currently using Periodic boundaries along the directions of NON-propagation and PML boundaries along the direction of propagation. I also have listed the script below if anyone is interested in the setup.<\/p>\n

 <\/p>\n

selectall; deleteall; clear;<\/p>\n

 <\/p>\n

 <\/p>\n

slab_x=20e-9;<\/p>\n

slab_yz=100e-9;<\/p>\n

 <\/p>\n

#Setting up simulation region<\/p>\n

addfdtd;<\/p>\n

set(“background index”,1);<\/p>\n

set(“x min”,-slab_x\/2-5000e-9);<\/p>\n

set(“x max”,slab_x\/2+5000e-9);<\/p>\n

set(“y min”,-slab_yz\/2);<\/p>\n

set(“y max”,slab_yz\/2);<\/p>\n

set(“z min”,-slab_yz\/2);<\/p>\n

set(“z max”,slab_yz\/2);<\/p>\n

set(“x min bc”,”PML”);<\/p>\n

set(“x max bc”,”PML”);<\/p>\n

set(“y min bc”,”Periodic”);<\/p>\n

set(“y max bc”,”Periodic”);<\/p>\n

set(“z min bc”,”Periodic”);<\/p>\n

set(“z max bc”,”Periodic”);<\/p>\n

#set(“mesh type”,”uniform”);<\/p>\n

#set(“dx”,0.5e-9);<\/p>\n

#set(“dy”,5e-9);<\/p>\n

#set(“dz”,5e-9);<\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

#Setting Up Plane Wave<\/p>\n

addplane;<\/p>\n

set(“injection axis”,”x”);<\/p>\n

set(“x”,-slab_x\/2-3000e-9);<\/p>\n

set(“y min”,-slab_yz\/2);<\/p>\n

set(“y max”,slab_yz\/2);<\/p>\n

set(“z min”,-slab_yz\/2);<\/p>\n

set(“z max”,slab_yz\/2);<\/p>\n

set(“center wavelength”,1.55e-6);<\/p>\n

set(“wavelength span”,0.0e-6);<\/p>\n

 <\/p>\n

 <\/p>\n

#Setup Gold Material<\/p>\n

addrect;<\/p>\n

set(“x min”,-slab_x\/2);<\/p>\n

set(“x max”,slab_x\/2);<\/p>\n

set(“y min”,-slab_yz\/2);<\/p>\n

set(“y max”,slab_yz\/2);<\/p>\n

set(“z min”,-slab_yz\/2);<\/p>\n

set(“z max”,slab_yz\/2);<\/p>\n

set(“material”,”Au (Gold) – Palik”);<\/p>\n

 <\/p>\n

 <\/p>\n

#Setting Up Monitors R<\/p>\n

addpower;<\/p>\n

set(“Monitor Type”,”2D X-Normal”);<\/p>\n

set(“x”,-slab_x\/2-4000e-9);<\/p>\n

set(“y min”,-slab_yz\/2);<\/p>\n

set(“y max”,slab_yz\/2);<\/p>\n

set(“z min”,-slab_yz\/2);<\/p>\n

set(“z max”,slab_yz\/2);<\/p>\n

 <\/p>\n

#Setting Up Monitors R<\/p>\n

addpower;<\/p>\n

set(“Monitor Type”,”2D X-Normal”);<\/p>\n

set(“x”,slab_x\/2+4000e-9);<\/p>\n

set(“y min”,-slab_yz\/2);<\/p>\n

set(“y max”,slab_yz\/2);<\/p>\n

set(“z min”,-slab_yz\/2);<\/p>\n

set(“z max”,slab_yz\/2);<\/p>\n

 <\/p>\n

 <\/p>\n

#Adding Movie<\/p>\n

addmovie;<\/p>\n

set(“x min”,-slab_x\/2-5000e-9);<\/p>\n

set(“x max”,slab_x\/2+5000e-9);<\/p>\n

 <\/p>\n","protected":false},"template":"","class_list":["post-355783","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t