UV light-induced atom desorption for magnetic trap in single vacuum chamber

UV (390nm) light was used to modulate the rubidium partial pressure by inducing desorption of Rb atoms from the inner walls of the vacuum cell. A few mW/cm 2 of UV light was enough to increase the rubidium partial pressure by a factor of 30 in about 1 s. After the source was turned off, the pressure quickly decayed back to its previous value with a time constant as short as 120 ms, allowing for long tapping lifetimes after the MOT holding phase. The number-lifetime product of the magnetic trap was shown as a function of the duration of the MOT holding phase, the maximum value was achieved after a MOT holding time of 1.25 s.