Thermally induced nonlinear optical absorption in metamaterial perfect absorbers

Journal Article · Mon Mar 16 00:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4914451· OSTI ID:22395750

Guddala, Sriram; Kumar, Raghwendra; Ramakrishna, S. Anantha ^[1]

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1. Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016 (India)

A metamaterial perfect absorber consisting of a tri-layer (Al/ZnS/Al) metal-dielectric-metal system with top aluminium nano-disks was fabricated by laser-interference lithography and lift-off processing. The metamaterial absorber had peak resonant absorbance at 1090 nm and showed nonlinear absorption for 600ps laser pulses at 1064 nm wavelength. A nonlinear saturation of reflectance was measured to be dependent on the average laser power incident and not the peak laser intensity. The nonlinear behaviour is shown to arise from the heating due to the absorbed radiation and photo-thermal changes in the dielectric properties of aluminium. The metamaterial absorber is seen to be damage resistant at large laser intensities of 25 MW/cm{sup 2}.

• OSTI ID: 22395750
• Journal Information: Applied Physics Letters, Vol. 106, Issue 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
ALUMINIUM
DAMAGE
DIELECTRIC MATERIALS
DIELECTRIC PROPERTIES
HEATING
INTERFERENCE
LASER RADIATION
LAYERS
NONLINEAR PROBLEMS
SPECTRAL REFLECTANCE
WAVELENGTHS
ZINC SULFIDES