| 摘要 |
<p>Apparatus for generating a reference frequency, comprising means for generating electromagnetic coherent radiation used for exciting two hyperfine atomic levels of a material in order to cause a Coherent Population Trapping phenomenon to occur and to measure the frequency of a radiation emitted by said material in consequence of the excitation, in order to use such frequency as reference frequency. According to the invention, the two hyperfine levels are chosen apt to originate a transition (D1) in said material, to which transition a symmetrical dipole matrix (DM) is associated, in order to reduce the frequency shift and asymmetries in reference frequency (CK).</p> |
