Reproducible emission from nonlinear random lasers

Journal Article · 26 December 2024 · Optics Communications

DOI: https://doi.org/10.1016/j.optcom.2024.131426 · OSTI ID:2520594

Andreasen, Jonathan  ^[1]; Robertson, Wesley D. ^[1]; Brown, Roger ^[1]; Shank, Josh ^[2]; Kaehr, Bryan ^[2]; Henry, David ^[2]; Smith, Sean ^[2]; Spoerke, Eric ^[2]; Scrymgeour, David A. ^[2]

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1. Georgia Inst. of Technology, Atlanta, GA (United States). Georgia Tech Research Institute
2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Multiple scattering of light serves as a mechanism for feedback in random lasers. Consequently, internal spatial mode patterns, lasing wavelengths, and output directionality can all be random. Strong mode interaction can occur in such devices due to spatially overlapping modes resulting in nonlinearity with respect to the pump input power. Nevertheless, temporal coherence and lasing mode amplitude can be fixed at a constant pumping rate. This is a property desirable for applications where unique randomness is exploited but expected to be reliable over time, such as physical unclonable functions. Random lasers can also be cheaply and easily fabricated, exhibit relatively low lasing thresholds and high emission intensity. However, the precise scattering properties of such structures and fluctuations in the pump field can make device emission irreproducible, thereby limiting random laser applications. Here, in this work, we directly compare the random lasing spectra from zinc oxide samples fabricated in four distinct ways: spin-coating, sputtering, solgel deposition, and atomic layer deposition. The particular method of fabrication has a strong impact. Samples made through atomic layer deposition here exhibit both reproducibility and strong nonlinearity desirable for applications. Randomness in emission spectra persists across hundreds of repeated and averaged measurements irrespective of spatial location and is demonstrably nonlinear with respect to input signal intensity.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
• Grant/Contract Number: NA0003525
• OSTI ID: 2520594
• Report Number(s): SAND--2025-02041J
• Journal Information: Optics Communications, Journal Name: Optics Communications Vol. 578; ISSN 0030-4018
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English