Manijeh Razeghi, from the McCormick school of engineering and applied science at Northwestern University, led the study which could allow scientists in the future to incorporate quantum cascade lasers into applications such as remote sensing of hazardous chemicals.
She noted that the team was able to create diodes that produce more light than heat, which is the most significant breakthrough for her.
Ms Razeghi explained: "Passing the 50 per cent mark in efficiency is a major milestone and we continue to work to optimise the efficiency of these unique devices."
Quantum cascade lasers differ to conventional lasers in that they only require electrons to operate, since they are unipolar.
A recent study at Arizona State University achieved diode capability in its development of a new stackable memory device by replacing a layer of metal with doped silicon.
