| As part of the ongoing world-wide effort in improving time and frequency references, a high accuracy optical frequency standard was developed using the electric quadrupole allowed 5s 2 S1/2 → 4d 2 D5/2 clock transition at 445 THz (674 nm) in a trapped and laser cooled 88Sr+ ion. An ion trap system of the endcap design has been recently evaluated with a fractional frequency uncertainty which surpasses the accuracy of the current realization of the SI second. This thesis seeks to further evaluate the limiting systematic shifts of the device by optimizing a second ion trap reference based on a rf Paul trap design, which was then compared with the endcap trap reference frequency. The comparison of the two ion traps' reference frequencies confirmed an overal offset of --0.36 +/- 0.08 Hz at the 445 THz reference frequency corresponding to a fractional frequency offset of 8 x 10--16 . |
