Single Trapped 171Yb+ for Optical Frequency Standards

An optical clock or frequency standard based on the interrogation of an atomic transition in the optical domain, operates at-1014 Hz is capable of providing orders of magnitude better accuracy than the present primary standard of frequency or time operating in the microwave range. Optical transitions of an ions, confined within a radio frequency ion trap and laser cooled to $\sim \mathrm {m}\mathrm {K}$temperature, provides better long term stability since they are free from Coulomb and intra-atomic interactions. Optical frequency standards have been realized with several ions, e.g., ¹⁹⁹Hg⁺, ¹⁷¹Yb⁺, ¹¹⁵In⁺, ⁸⁸Sr⁺, ⁴⁰Ca⁺, ²⁷Al⁺ and among those ¹⁷¹Y⁺ has multiple ultra-narrow optical transitions suitable for serving as frequency standards [1–2]