1. Wavelength stability: Torus 532 vs unlocked SLM lasers
± 2pm drift - SLM locked Torus
What happens to the longitudinal mode of the locked Torus
when the ambient temperature is changed from 20°C to 40°C?
± 10pm drift – unlocked laser*
Here is the Torus - linewidth <1MHz
λ drift of ±2pm over 20°C ambient change
Even over a wide temperature change,
the locked Torus remains very stable
with very low drift
How does an unlocked SLM laser behave?
±10pm drift will result in several mode-hops
of the unlocked SLM laser
*Cobolt Samba specification sheet

2. 1 MHz linewidth drifting by ± 10pm* drift equates to 21GHz
How does an unlocked SLM laser compare with the Ventus?
Ventus Bandwidth = 30GHz
How does the unlocked SLM
laser perform?
Unlocked SLM laser can drift – whilst mode-hopping - almost as much as the entire bandwidth of the Ventus laser
with ~8 lasing modes
Ventus bandwidth is stable:
peak drifts <± nm**
cannot ‘mode-hop’
frequency is defined by gain bandwidth – cannot drift like the unlocked SLM laser
Frequency
1 MHz linewidth drifting by ± 10pm* drift equates to 21GHz
*Cobolt Samba specification sheet
**measured with stabilised He-Ne locked to iodine cell