Fig. 1. Simulation of photothermal conversion. (a)-(c) Localized surface plasmon resonance induced electric field enhancement of nanoprobe with single gold nanosphere, equilateral trangular gold nanosphere trimer, and densely packed hexagonal gold nanosphere heptamer, respectively; (d) simulated optical heat power of nanoprobe with different coupling nanostructures; (e) simulated maximum optical heat power per nanosphere in nanoprobe with different coupling nanostructures

Fig. 2. Simulation of thermal diffusion. (a)-(c) Simulated quantitative temperature fields of nanoprobe with single gold nanosphere, equilateral trangular gold nanosphere trimer, and densely packed hexagonal gold nanosphere heptamer after irradiation for 10 ns by laser with electric field intensity of 4×10⁵ V/m; (d) temperature distribution along the dotted lines in figures (a)-(c); (e) maximum temperature of nanoprobes with different coupling nanostructures after irradiation for 10 ns by laser

Fig. 3. Influence of nanosphere-nannosphere gap (d) on nanoprobe performance. (a)-(c) Localized surface plasmon resonance induced electric field enhancement of gold nanosphere heptamer probe with nanosphere-nanosphere gap distance of 2, 1, and 0.5 nm; (d) simulated optical heat power of gold nanosphere heptamer probe with different gaps; (e)-(g) simulated quantitative temperature fields of gold nanosphere heptamer probe with different gaps after irradiation for 10 ns by a laser with electric field intensity of 4×10⁵ V/m; (h) temperature distribution along the dotted lines in figures (e)-(g)

Fig. 4. Influence of single-sphere diameter on nanoprobe performance. (a)-(c) Localized surface plasmon resonance induced electric field enhancement of gold nanosphere heptamer probe with single-sphere diameter of 15, 30, and 60 nm; (d)-(f) simulated quantitative temperature fields of gold nanosphere heptamer probe with different single-diameter after irradiation for 10 ns by a laser with electric field intensity of 4×10⁵ V/m; (g) simulated optical heat power per volume of gold nanosphere heptamer probe with different single-sphere diameters; (h) temperature distribution along the dotted lines in figures (d)-(f)

Fig. 5. Influence of particle shape on nanoprobe performance. (a)-(c) Localized surface plasmon resonance induced electric field enhancement of gold nano heptamers probe with spherical, hexagonal prismatic and cube particles; (d)-(f) simulated quantitative temperature fields of gold nano heptamers probe with different shapes of particles after irradiation for 10 s by a laser with electric field intensity of 4×10⁵ V/m; (g) simulated optical heat power per volume of gold nano heptamers probe with different shapes of particles; (h) temperature distribution along the dotted lines in figures (d)-(f)

Fig. 6. Influence of permutation mode on nanoprobe performance. (a)-(c) Localized surface plasmon resonance induced electric field enhancement of nanoprobe constituted by nanoparticles with densely packed hexagonal heptamer, ring shape, and long chain; (d) simulated optical heat power of nanoprobe with different permutation modes; (e)-(g) simulated quantitative temperature fields of gold nanoprobe with different permutation modes after irradiation for 10 ns by a laser with electric field intensity of 4×10⁵ V/m; (h) temperature distribution along the dotted lines in figures (e)-(g)

Fig. 7. Aggregation enhancement of platinum nanospheres. (a) Electric field distribution of platinum nanosphere; (b) electric field enhancement for platinum nanospheres after aggregation into heptamer; (c) simulated optical heat power per platinum nanospheres before and after aggregation into heptamer; (d) percentage increase of optical heat power per gold or platinum nanosphere after aggregation into heptamer