اﺳﺘﻔﺎده از ﻧﺎﻧﻮﭘﯿﮑﺴﻞ ﻫﺎي ﭘﻼﺳﻤﻮﻧﯿﮑﯽ ﺑﺮاي ﮐﺎرﺑﺮدﻫﺎي اﻣﻨﯿﺘﯽ

Plasmonic Nano-pixels for Security Applications

در اﯾﻦ ﻣﻘﺎﻟﻪ از ﻧﺎﻧﻮروزﻧﻪ ﻫﺎي ﭘﻼﺳﻤﻮﻧﯿﮑﯽ ﺑﺮاي ﺳﺎﺧﺖ ﭘﯿﮑﺴﻞ ﻫﺎي ﺗﻤﺎم رﻧﮕﯽ ﺑﺎ رزوﻟﻮﺷﻦ ﻧﺎﻧﻮﻣﺘﺮي اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. در اﯾﻦ ﻓﻨﺎوري ﺑﺎ ﺗﺮﮐﯿﺐ ﻧﺎﻧﻮﻟﯿﺘﻮﮔﺮاﻓﯽ ﺑﺎرﯾﮑﻪ اﻟﮑﺘﺮوﻧﯽ و زداﯾﺶ ﺧﺸﮏ اﻣﮑﺎن اﯾﺠﺎد ﻧﺎﻧﻮروزﻧﻪ ﻫﺎي ﭘﻼﺳﻤﻮﻧﯿﮑﯽ در ﻻﯾﻪ ﻫﺎي ﻧﺎزك آﻟﻮﻣﯿﻨﯿﻮم ﻓﺮاﻫﻢ ﮔﺸﺘﻪ ﮐﻪ ﺑﻌﻨﻮان ﻧﺎﻧﻮﭘﯿﮑﺴﻞ ﻫﺎي رﻧﮕﯽ ﻋﻤﻞ ﻣﯽ ﮐﻨﻨﺪ. ﺑﺎ ﺗﺮﮐﯿﺐ آراﯾﻪ اي از اﯾﻦ ﻧﺎﻧﻮروزﻧﻪ ﻫﺎ ﺑﺎ اﺑﻌﺎد و ﺗﻮاﻟﯽ ﻣﺨﺘﻠﻒ ﻧﺎﻧﻮﭘﯿﮑﺴﻞ ﻫﺎي ﺗﻤﺎم رﻧﮕﯽ ﮐﻪ ﻗﺎﺑﻠﯿﺖ ذﺧﯿﺮه اﻃﻼﻋﺎت را دارﻧﺪ اﯾﺠﺎد ﺷﺪ. ﻋﻼوه ﺑﺮ اﯾﻦ، ﺑﺎ اﺳﺘﻔﺎده از روش ﺗﻔﺎﺿﻞ ﻣﺤﺪود ﺣﻮزه زﻣﺎن ﺗﻮزﯾﻊ ﻣﯿﺪان اﻟﮑﺘﺮﯾﮑﯽ و ﻗﺎﻧﻮن اﻧﺘﺨﺎب در اﯾﻦ ﻧﺎﻧﻮروزﻧﻪ ﻫﺎ ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ و ﺑﺎ ﻧﺘﺎﯾﺞ ﺗﺠﺮﺑﯽ ﻣﻘﺎﯾﺴﻪ ﺷﺪ. اﻣﮑﺎن ﺟﻌﻞ ﭼﻨﯿﻦ ﺳﻄﻮﺣﯽ ﺑﻪ دﻟﯿﻞ داﺷﺘﻦ اﺑﻌﺎد ﻧﺎﻧﻮﻣﺘﺮي و ﻋﺪم دﺳﺘﺮﺳﯽ ﻋﻤﻮﻣﯽ ﺗﺠﻬﯿﺰات ﺳﺎﺧﺖ وﺟﻮد ﻧﺪارد و ﺑﺮاي ﮐﺎرﺑﺮدﻫﺎﯾﯽ اﻣﻨﯿﺘﯽ ﻫﻤﭽﻮن ﺳﺎﺧﺖ ﮐﺎرت ﻫﺎي اﻋﺘﺒﺎري و ﭘﻮل ﻣﻨﺎﺳﺐ ﻫﺴﺘﻨﺪ.

In this paper, we developed full-color nano-pixels with a nanoscale resolution based on plasmonic nano-slits. For this purpose, we combine electron beam lithography and dry etching nanotechnologies to nanofab-ricate plasmonic nano-slits behaving as polarization-dependent nano-pixels. Arrays of this nano-pixels with dif-ferent lengths and periods are used for generation of different colors and consequently storing information. In addition, finite-difference time domain method is used to investigate the selection rule and the electric field dis-tributions in these plasmonic nano-slits and compared them with the experimental results. It is revealed that the electric field distribution is perpendicular to the polarization of the excitation white light and the concentration is on the sharp edges close to the center of the nano-slits on the top and the bottom sides. These plasmonic surfaces are promising for anti-counterfeiting applications due to their nanoscale details, lack of the public access to the fabrication equipment and fabrication expertise. Therefore, these plasmonic surfaces have a great potential to be used for development of the next generation of credit cards, security labels and bank notes.