Low resistance wavelength-reproducible p-type (Al,Ga)As distributed Bragg reflectors grown by molecular beam epitaxy

Abstract

We report the reproducible molecular beam epitaxial growth of Be‐doped piecewise linearly graded (Al,Ga)As distributed Bragg reflectors that have vertical series resistivities near bulk values. For mirrors with three linear segments per interface, the center wavelength reproducibility is 0.1% and the series resistivity is as low as 1.8×10⁻⁵ Ω cm² for hole concentrations of 5×10¹⁸ cm⁻³. Measured reflectivities of 6.0% per interface are comparable to conventional single‐linear‐grade mirrors. Vertical‐cavity surface‐emitting lasers incorporating these mirrors exhibit record‐low voltage thresholds of less than 1.5 V.