An optical scheme for stable two-color operation from a single laser diode (LD) by means of a multiplexed reflective Bragg mirror is proposed and demonstrated. A mode spectral separation of ~ 3 nm (1 THz) and laser linewidth less than 80 pm, with sidemode suppression ratio over 24 dB, and an output power of 1.7 W are achieved with a monolithic dual-wavelength Bragg mirror. Temperature stability of spectral locking of an LD in dual-wavelength operation is presented.