Nanoscale Broadband Deep-Ultraviolet Light Source from Plasmonic Nanoholes

• DOI: 10.1021/acsphotonics.9b00127
• Publication Date: 2019-03-07T18:59:24Z
• Authors: Liping Shi; José R. C. Andrade; Juemin Yi; Marius Marinskas; Carsten Reinhardt; Euclides Almeida; Uwe Morgner; Milutin Kovacev
• Keywords: Ultraviolet

We employ a broadband Ti:sapphire femtosecond oscillator to simultaneously launch two localized surface plasmon modes in rectangular plasmonic nanoholes. The resonant frequencies of these match well with our laser spectrum. As result, the nanoholes do not only efficiently boost third harmonic radiation intensity, but also significantly broaden harmonic's bandwidth, producing nanoscale deep-ultraviolet light source range 240 300 nm. Due involvement modes, beam becomes elliptically polarized and reaches its maximum intensity when polarization direction is 60° respect long edges, rather than commonly used 90°.