Randomized whispering-gallery-mode microdisk laser arrays via cavity deformations for anti-counterfeiting labels

Abstract

Optical physical unclonable functions (PUFs) have emerged as a promising strategy for effective and unbreakable anti-counterfeiting. However, the unpredictable spatial distribution and broadband spectra of most optical PUFs complicate efficient and accurate verification in practical anti-counterfeiting applications. Here, we propose an optical PUF-based anti-counterfeiting label from perovskite microlaser arrays, where randomness is introduced through vapor-induced microcavity deformation. The initial perovskite microdisk laser arrays with regular positions and uniform sizes are fabricated by femtosecond laser direct ablation. By introducing vapor fumigation to induce random deformations in each microlaser cavity, a laser array with completely uneven excitation thresholds and narrow-linewidth lasing signals is obtained. As a proof of concept, we demonstrated that the post-treated laser array can provide fixed-point and random lasing signals to facilitate information encoding. Furthermore, different emission states of the lasing signal can be achieved by altering the pump energy density to reflect higher capacity information. A threefold PUF (excited under three pump power densities) with a resolution of 5×5 pixels exhibits a high encoding capacity (1.43×1045), making it a promising candidate to achieve efficient authentication and high security with anti-counterfeiting labels.

Continuous-Wave Pumped Monolayer WS2 Lasing for Photonic Barcoding

“…Conversely, laser-based barcodes offer clear advantages with their narrow linewidth and brightness, making them reliable for identification. Researchers are exploring micro/nanolaser-based barcodes with different structures, like Whispering Gallery Mode (WGM) and Fabry-Perot [8][9][10][11][12][13]. However, these laser systems usually need expensive pulsed lasers for detection, obstructing their practicality.…”

Dynamic Physical Unclonable Function Relying on Lasing Polarization

“…The multidimensional information encryption of thermal response circularly polarized laser arrays was realized by using wavelength and polarization state as cryptographic primitives . In addition, perovskite − microsphere lasing is often based on the whispering gallery mode (WGM), which confines light to a tiny volume, providing a high-quality factor and low threshold, and has been applied in PUFs. ,− The WGM cavity’s lasing mode is highly sensitive to the microcavity’s geometry owing to its total internal reflection; thus, by varying the microcavity’s boundary, multiple lasing signals can be generated. ,,, The destruction of the micronanostructure symmetry generates degenerate detuning of the WGM cavity, which results in linear polarization characteristics and the mode shift of lasing. ,− These phenomena contribute to unpredictable and arbitrary spectra at any polarization angle and may be promising candidates to realize dynamic PUF and break through the bottleneck of the current dynamic PUFs.…”

“…28,31−33 The WGM cavity's lasing mode is highly sensitive to the microcavity's geometry owing to its total internal reflection; thus, by varying the microcavity's boundary, multiple lasing signals can be generated. 8,21,28,34 The destruction of the micronanostructure symmetry generates degenerate detuning of the WGM cavity, which results in linear polarization characteristics and the mode shift of lasing. 22,35−39 These phenomena contribute to unpredictable and arbitrary spectra at any polarization angle and may be promising candidates to realize dynamic PUF and break through the bottleneck of the current dynamic PUFs.…”