We present recent progress in the growth of nitride based laser diodes (LDs) made by Plasma Assisted Molecular Beam Epitaxy (PAMBE). In this work we demonstrate continuous wave (cw) LDs grown by PAMBE operating in the range 430-460 nm. The LDs were grown on c-plane bulk GaN substrates with threading dislocation densities (TDDs) ranging from 10(3) cm(-2) to 10(7) cm(-2). The low TDDs allowed fabrication of cw LDs with the lifetime exceeding 2000 h at 10 mW of optical output power. The maximum output power for these LDs was 80 mW. We used AlGaN cladding-free design of LDs with InGaN waveguides. The key element to achieve lasing for wavelengths above 450 nm was substantial increase of the nitrogen flux available for growth in PAMBE. The increase of N flux is beneficial for growth of efficient InGaN QWs, which allowed demonstration of optically pumped lasing from single quantum well InGaN laser structures at 501 nm. (c) 2013 Elsevier B.V. All rights reserved.