Towards sympathetic cooling of trapped ions with laser- cooled Mg+ ions for mass spectrometry and laser spectroscopy Radu Cazan

The Purpose Setup of a system for cooling ions in a trap to a very low temperature, regardless of their - charge state, - energy level structure or - other parameters -> sympathetic cooling by laser cooled Mg ions. M. Bussmann, Int.J.MassSpec. 251, 179(2006)

Cooling techniqueLimit Temperature (typ.)Cooling Time Resistive Cooling~ 4 K> 1 s Buffer Gas Cooling~ 4 K~10 – 100 ms Electron Cooling< 1 K~100 ms – 1 s Laser Cooling~ 1 – 10 mK (ħΓ/2k B )~ 1 ms Sympathetic Cooling< 0.25 K~ 1 ms Sisyphus Cooling ~ μK ~ 1 ms An overview of cooling techniques

First resonator

for P 1118 =970 mW ~775 mW coupled P 559 =325 mW Enhancement factor A~40-60

First resonator - resized & refurbished laser for P 1118 ~1050 mW ?% ASE & 2 nd mode P 559 = mW P=1.85 W in two modes W A.S.E. Maximum c.e.~57% =>P 1118 ~600 mW Smaller cavity: + increased FSR = + increased bandwidth + better stability - up to 10% less output in our case

Second resonator

P 279 =16.7 mW max ~15 mW average for P 559 ~210 mW ~170 mW coupled Enhancement factor A~60-70