Giant enhancement of two photon induced luminescence in metal nanostructure

Abstract

We experimentally demonstrate a drastic increase in the rate of radiative process of a nanoscale physical system with implementation of the three physical effects: (1) the size effect, (2) plasmon resonance and (3) the optical Tamm state. As an example of a nanoscale physical system, we choose a single nanohole in Au film when the nanohole is embedded in a photonic crystal of a specific type that maintains an optical Tamm state and as a radiative process - a nonlinear photoluminescence. The efficiency of the nonlinear photoluminescence is increased by more than 10(7) times in compare to a bulk material.

Multiphoton imaging of melanoma 3D models with plasmonic nanocapsules

“…The field of applications for NPs responsive to two-photon excitation (2PE) include photoluminescence for bioimaging with/without heat production for photothermal therapy [23][24][25][26] , ROS formation for photodynamic therapy [27] , and photo-triggered drug release for chemo-photothermal therapy [ 28 , 29 ]. Two-photon luminescence (2PL) is based on the use of two photons of low energy pulsed at the femtosecond range; they are absorbed by the nanomaterial, leading to its excitation with the double of the initial energy [30] . The use of low-energy near infrared (NIR) photons improves tissue penetration (up to 1 mm thick [ 25 , 31 ]) in the socalled biological optical window where the absorption and scattering of water and tissue pigments (hemoglobin, melanin, among others) are minimal [ 32 , 33 ].…”

Interband transition enhanced third harmonic generation from nanoplasmonic gold‏

“…Nonlinear plasmonics brings the functionality of nonlinear optics, including wavelength conversion and switching, to the nanoscale [1][2][3][4][5][6]. The goal is to obtain efficient light energy conversion or optical functionality at the subwavelength scale [7][8][9][10][11][12][13][14][15][16]. This is in contrast to conventional nonlinear optics, which typically requires phase matching over long distances or microcavities to obtain high conversion efficiency [17][18][19][20][21].…”

Nonclassical Optical Properties of Mesoscopic Gold

“…In absence of a distinct plasmonic resonance, the emitted photons exhibit the energy of the interband transitions involved in the last step [29]. It is important to note that due to the fact that the first step involves intraband transitions, which require a source of momentum to enable the electrons changing their energy, 2PPL in noble metals is expected to only occur in nanostructured materials or materials with significant roughness because of the resulting strong light confinement [32] and to be absent in flat thin films [33].…”