Smart Healthcare & Device Research Center, Samsung Medical Center , 81 Irwon-ro, Gangnam-gu, Seoul 06351, Republic of Korea.
Samsung Advanced Institute for Health Sciences & Technology (SAIHST), SungKyunKwan University , 81 Irwon-ro, Gangnam-gu, Seoul 06351, Republic of Korea.
ACS Appl Mater Interfaces. 2017 Oct 25;9(42):37154-37159. doi: 10.1021/acsami.7b10715. Epub 2017 Oct 12.
Unlike monometallic materials, bimetallic plasmonic materials offer extensive benefits such as broadband tuning capability or high environmental stability. Here we report a broad range tuning of plasmon resonance of alloyed nanoislands by using solid-state dewetting of gold and silver bilayer thin films. Thermal dewetting after successive thermal evaporation of thin metal double-layer films readily forms AuAg-alloyed nanoislands with a precise composition ratio. The complete miscibility of alloyed nanoislands results in programmable tuning of plasmon resonance wavelength in a broadband visible range. Such extraordinary tuning capability opens up a new direction for plasmonic enhancement in biophotonic applications such as surface-enhanced Raman scattering or plasmon-enhanced fluorescence.
与单金属材料不同，双金属等离子体材料具有广泛的优势，如宽带调谐能力或高环境稳定性。在这里，我们报告了通过使用金和银双层薄膜的固态去湿来实现合金纳米岛的等离子体共振的宽范围调谐。在薄金属双层薄膜连续热蒸发之后进行热去湿，容易形成具有精确组成比的 AuAg 合金纳米岛。合金纳米岛的完全混溶性导致在宽带可见范围内的等离子体共振波长的可编程调谐。这种非凡的调谐能力为生物光子学应用中的等离子体增强开辟了新的方向，例如表面增强拉曼散射或等离子体增强荧光。
