Optical Clock with Ultracold Neutral Atoms

Abstract

We demonstrate how to realize an optical clock with neutral atoms that is competitive to the currently best single ion optical clocks in accuracy and superior in stability. Using ultracold atoms in a Ca optical frequency standard, we show how to reduce the relative uncertainty to below 10(-15). We observed atom interferences for stabilization of the laser to the clock transition with a visibility of 0.36, which is 70% of the ultimate limit achievable with atoms at rest. A novel scheme was applied to detect these atom interferences with the prospect to reach the quantum projection noise limit at an exceptional low instability of 4 x 10(-17) in 1 s.

Frequency Metrology with Optical Lattice Clocks

“…45,46) Among these recommendations, optical standards based on single trapped ions 6) and ultracold neutral atoms in free fall 47,48) provided record levels of performance that approach those of the best Cs fountain clocks early in this century. Both of these single-ion and neutral-atom standards have advantages and disadvantages.…”

“…In this viewpoint, singly trapped ions in an RF quadrupole field 6) and ultracold neutral atoms in free fall 48) are expected to be the best realization of atomic clocks. In striking contrast with these traditional approaches, the optical lattice clocks utilize well-controlled perturbation applied on the atoms.…”

Comparison of different techniques in optical trap for generating picokelvin 3D atom cloud in microgravity

“…First, a picokelvin atom system can provide us with an experimental ultracold environment with slower atom velocities and a longer observable life [14]. Secondly, ultralow temperatures are useful for researching precision measurements, quantum information and quantum optics systems [11,[16][17][18][19]. Finally, such low temperature systems enable us to observe special phenomena that only occur at ultralow energy scales, such as phase transitions [4].…”

Prospects for milli-hertz linewidth lasers using collective emission

“…Ultra-stable lasers are central for clocks [1], [2], [3], [4], [5], precision spectroscopy [6], and clock comparisons [7]. The most stable lasers achieve line widths of order ≲ 1 Hz corresponding to a quality factor of ∼ 10 15 [8].…”