A cost-effective isolation technique using laser treatment is proposed to suppress the undesired crosstalk between dual power amplifiers (PAs), which are essential to multiple-input multiple-output communications system. Laser treatment not only reduces the small-signal coupling between dual PAs but also enhances the linearity of the PA under dual-PA operation mode. The figure of merit for the small-signal coupling has an improvement of 4.55 dB at 2.45 GHz, and the output power at 3% ( 30 dB) error vector magnitude (EVM) has a linearity improvement of 6.1 dB under 0-dB interference.Index Terms-Coupling, crosstalk, isolation, laser treatment, multiple input multiple output (MIMO), power amplifiers (PAs).