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Iodine frequency-stabilized HeNe laser amplified by injection locking of a semiconductor laser diode

The realisation of the metre definition is still today mostly performed using iodine frequency-stabilized HeNe lasers. Unfortunately, they deliver little optical power. Instead of migrating to other expensive laser technologies, the use of an injection locked semiconductor laser is proposed in order to boost the optical output of the legacy HeNe laser primary reference. The characterisation of the system and its validation through a comparison measurement is reported whereby no impact on the frequency and the stability of the HeNe reference laser could be observed.