Encoding Random Hot Spots of a Volume Gold Nanorod Assembly for Ultralow Energy Memory

Abstract

Data storage with ultrahigh density, ultralow energy, high security, and long lifetime is highly desirable in the 21st century and optical data storage is considered as the most promising way to meet the challenge of storing big data. Plasmonic coupling in regularly arranged metallic nanoparticles has demonstrated its superior properties in various applications due to the generation of hot spots. Here, the discovery of the polarization and spectrum sensitivity of random hot spots generated in a volume gold nanorod assembly is reported. It is demonstrated that the two-photon-induced absorption and two-photon-induced luminescence of the gold nanorods adjacent to such hot spots are enhanced significantly because of plasmonic coupling. The polarization, wavelength, and spatial multiplexing of the hot spots can be realized by using an ultralow energy of only a few picojoule per pulse, which is two orders of magnitude lower than the value in the state-of-the-art technology that utilizes isolated gold nanorods. The ultralow recording energy reduces the cross-talk between different recording channels and makes it possible to realize rewriting function, improving significantly both the quality and capacity of optical data storage. It is anticipated that the demonstrated technology can facilitate the development of multidimensional optical data storage for a greener future.

Plasmonic Refractive Index Sensors Based on One- and Two-Dimensional Gold Grating on a Gold Film

“…The electric field enhancement [6][7][8] and strong absorption [9,10] caused by the local surface plasmons are widely used in surface-enhanced Raman scattering [11][12][13] and enhanced absorption [14,15]. In addition, the unique optical properties of surface plasmons have a wide range of applications in photocatalysis [16][17][18][19][20], absorber [21][22][23][24], photolithography [25][26][27][28], filter [29,30], optical data storage [31,32], and other fields [33][34][35][36]. At present, one of the most important researches focusing on surface plasmons is refractive index sensing [37][38][39][40][41][42].…”

Femtosecond Photon‐Mediated Plasma Enhances Photosynthesis of Plasmonic Nanostructures and Their SERS Applications

“…Plasmonic nanostructures, capable of strong interaction with incident light by exciting localized surface plasmon resonance (LSPR), have attracted numerous interests in the fields of plasmon‐enhanced spectroscopies, imaging, chemical transformations, and solar energy conversion. [3c,d] Notably, the enhanced‐electromagnetic field (“hot spots”) near plasmonic surfaces because of strong plasmon resonance coupling fully benefits to magnify the cross‐section of surface‐enhanced Raman spectroscopy (SERS)[1b,c,4] and extended applications .…”

Reversible decryption of covert nanometer-thick patterns in modular metamaterials

“…Most of the recently developed optical security features address both authentication and data encryption functions and take advantage of the advancements in the microfabrication techniques. A variety of optical phenomena are used for these reports, including optical interference [4,5], plasmonics [6][7][8][9][10][11][12], photonic crystals [13][14][15], holograms [16,17], dielectric metasurfaces [18], luminescence [19], and Pauli blocking [20]. The encrypted patterns in these reports are created using optical or e-beam lithography [5][6][7][8]10,11,[16][17][18], ultraviolet radiation [4,13], O 2 plasma [14], laser scanning [9], printing on paper [20], stamping [12,15], and stenciling [5].…”

“…A variety of optical phenomena are used for these reports, including optical interference [4,5], plasmonics [6][7][8][9][10][11][12], photonic crystals [13][14][15], holograms [16,17], dielectric metasurfaces [18], luminescence [19], and Pauli blocking [20]. The encrypted patterns in these reports are created using optical or e-beam lithography [5][6][7][8]10,11,[16][17][18], ultraviolet radiation [4,13], O 2 plasma [14], laser scanning [9], printing on paper [20], stamping [12,15], and stenciling [5]. The patterns are then decrypted (or encrypted, if they are decrypted as fabricated) by applying humidity [4,14], magnetic field [13], spectroscopic scanning [6], polarized laser light [9,16], exposure to O 2 ∕H 2 gases [7,17], changing the refractive index of the medium [18], applying electrical signal [20], and observing the thermal image …”

“…The encrypted patterns in these reports are created using optical or e-beam lithography [5][6][7][8]10,11,[16][17][18], ultraviolet radiation [4,13], O 2 plasma [14], laser scanning [9], printing on paper [20], stamping [12,15], and stenciling [5]. The patterns are then decrypted (or encrypted, if they are decrypted as fabricated) by applying humidity [4,14], magnetic field [13], spectroscopic scanning [6], polarized laser light [9,16], exposure to O 2 ∕H 2 gases [7,17], changing the refractive index of the medium [18], applying electrical signal [20], and observing the thermal image [5,10,11]. Despite these successful demonstrations, the adaptation of these techniques into practice is limited mainly due to the scaling issues associated with the low yield and the need for sophisticated equipment during microfabrication or decryption/encryption.…”