Fig. 1. Measurement results of Au nanocages. (a) TEM image of Au nanocages; (b) absorption spectrum of Au nanocages

Fig. 2. Saturable absorption of Au nanocages SA

Fig. 3. Schematic diagram of passively Q-switched Ho³⁺/Pr³⁺ co-doped ZBLAN fiber laser using Au nanocages-based SA

Fig. 4. Performance of fiber laser based on Au nanocages SA. (a) Pulse trains; (b) optical spectrum (inset: frequency spectrum); (c) output power and pulse energy versus pump power; (d) repetition rate and pulse duration versus pump power