Flexible random lasers with tunable lasing emissions

Abstract

In this study, we experimentally demonstrated a flexible random laser fabricated on a polyethylene terephthalate (PET) substrate with a high degree of tunability in lasing emissions. Random lasing oscillation arises mainly from the resonance coupling between the emitted photons of gain medium (Rhodamine 6G, R6G) and the localized surface plasmon (LSP) of silver nanoprisms (Ag NPRs), which increases the effective cross-section for multiple light scattering, thus stimulating the lasing emissions. More importantly, it was found that the random lasing wavelength is blue-shifted monolithically with the increase in bending strains exerted on the PET substrate, and a maximum shift of ∼15 nm was achieved in the lasing wavelength, when a 50% bending strain was exerted on the PET substrate. Such observation is highly repeatable and reversible, and this validates that we can control the lasing wavelength by simply bending the flexible substrate decorated with the Ag NPRs. The scattering spectrum of the Ag NPRs was obtained using a dark-field microscope to understand the mechanism for the dependence of the wavelength shift on the exerted bending strains. As a result, we believe that the experimental demonstration of tunable lasing emissions based on the revealed structure is expected to open up a new application field of random lasers.

A random laser based on electrospun polymeric composite nanofibers with dual-size distribution

“…In search of exible coherent sources of light, cellulose or biomaterial substrates have been demonstrated using different fabrication methods and a combination of scatterers/gain media, including metallic nanoscatterers which can lead to scattering enhancement due to localized surface plasmons. [5][6][7][8][9][10][11][12][13][14] In particular, the use of electrospinning, a high electric eldbased technique that provides massive production of microand nanobers, represents a promising low cost method to be incorporated in integrated micro-and nanophotonic devices, 15 which can be used in exible matrices. These liform structures with a refractive index of about 1.5 provide waveguiding/ scattering along the bers as well as multidirectional propagation, due to their disordered structures 16 which depends on the ber diameter scale.…”

Toward Electrically Pumped Organic Lasers: A Review and Outlook on Material Developments and Resonator Architectures

“…Lee et al fabricated tunable random lasers with Rhodamine 6G (R6G) and silver nanoprisms on polyethylene terephthalate (PET) substrates based on the resonance coupling between the photons and localized surface plasmon. [ 150 ] In a recent report, [ 151 ] Li et al prepared a substrate with micropapilla surface structures from the natural lotus leaf via soft lithography. Well‐recognized random lasing peaks were achieved using 4‐(Dicyanomethylene)‐2‐ tert ‐butyl‐6(1,1,7,7‐tetramethyljulolidyl‐9‐enyl)‐4H‐pyran (DCJTB) as gain medium.…”

Robust and Flexible Random Lasers Using Perovskite Quantum Dots Coated Nickel Foam for Speckle‐Free Laser Imaging

“…Recently, extensive investigations have been concentrated on the realization of lasers on the plastic substrate due to their mechanical flexible characteristics suitable for the development of flexible optoelectronic systems. [1][2][3][4][5] For example, the deposition of ZnO nanoparticle embedded ZnO thin film on polycarbonate plastic substrate is proposed to realize flexible inorganic random lasers. [6] Organic lasers using solvent-free fluidic organic semiconductors as the gain medium, and highly flexible corrugated polymeric patterns and flexible polyurethane acrylate films as the resonator have also achieved mechanically single-mode tunable lasers.…”

“…[7] Furthermore, organic dye spin-coated on a polyethylene terephthalate substrate embedded with silver nanoprisms has fabricated flexible random lasers with a high degree of wavelength tunability over 15 nm through the influence of localized surface plasmon and random scattering under mechanical bending. [2] On the other hand, using organic polymers has shown the possibility to obtain mechanical flexibility and lightweight substrateless organic lasers that can be deposited on any surface. [8] Spin coating of strong adhesive perovskite thin films on flexible polyimide substrates has also obtained flexible random lasers with the control of excitation threshold through mechanical bending.…”