Controlled crystallization and engineering of the electro-optical properties of silver oxide nano/micro disks obtained by pulsed laser welding technique

Herein, Ag₂O films are subjected to the pulsed laser welding (PLW) technique to enhance their crystallinity and expand their application potential. Engineering the pulse energy and pulse width successfully produced Ag₂O nano/microdisks ranging in size from 100 to 900 nm. The crystallinity of the disks improved with increasing pulse energy and width. A significant reduction in defect concentration—by more than 61.5%—was achieved at 220 V and a pulse width of 10 ms. Optically, PLW enhanced transmittance and reduced the reflectance in Ag₂O films while lowering free carrier absorption. The energy band gap remained unchanged. As broadband antennas, the nano/microdisk-structured films operated effectively within the 2.3–5.1 GHz frequency range and exhibited a bandwidth of 2.8 GHz. They also showed a minimum return loss of − 38 dB at 3.15 GHz, confirming their suitability for mmWave applications.