Precision Metrology Meets Cosmology: Improved Constraints on Ultralight Dark Matter from Atom-Cavity Frequency Comparisons

Abstract

We conduct frequency comparisons between a state-of-the-art strontium optical lattice clock, a cryogenic crystalline silicon cavity, and a hydrogen maser to set new bounds on the coupling of ultralight dark matter to Standard Model particles and fields in the mass range of 10 −16 − 10 −21 eV. The key advantage of this two-part ratio comparison is the differential sensitivities to time variation of both the fine-structure constant and the electron mass, achieving a substantially improved limit on the moduli of ultralight dark matter, particularly at higher masses than typical atomic spectroscopic results. Furthermore, we demonstrate an extension of the search range to even higher masses by use of dynamical decoupling techniques. These results highlight the importance of using the best performing atomic clocks for fundamental physics applications as all-optical timescales are increasingly integrated with, and will eventually supplant, existing microwave timescales.

Thermal Noise in Cubic Optical Cavities

“…Ultra-stable lasers have many applications, such as frequency metrology [1][2][3][4][5], gravitational wave detection [6], fundamental physics tests [7,8], and coherent optical links [9,10]. A state-of-the-art ultra-stable laser shows that the linewidth is less than 10 mHz.…”

Simultaneous bicolor interrogation in thulium optical clock providing very low systematic frequency shifts

“…Modern optical clocks operating at the 10 −18 level of relative instability and uncertainty 6 – 14 stimulate discussion about inevitable redefinition of the SI second 15 , 16 , which is also motivated by comparisons of different types of optical clocks at the 10 −17 level 6 , 7 , 17 , 18 . Such performance allows one to accurately test some fundamental physical theories: general relativity 19 , 20 , Lorentz invariance 21 , 22 , drifts of fundamental constants 23 , 24 , and the search for dark matter particles 25 and dark matter clusters 26 .…”

Searching for Dark Matter with an Optical Cavity and an Unequal-Delay Interferometer

“…Amongst the various DM models, ultralight DM scenarios have recently seen a strong surge thanks to the excellent sensitivities provided by the latest advances in time and frequency metrology [3][4][5][6][7][8][9][10][11][12][13][14][15][16]. In such class of models, DM is made of a scalar field (SF) nonuniversally coupled to the standard model.…”

“…Typically, this SF will undergo oscillations that will be reflected through an oscillation of the fundamental constants of nature, a signature of a violation of the equivalence principle. This has motivated experimental searches for harmonic variations of the constants of nature in a wide range of frequencies: with atomic clocks in the 10 −10 -1 Hz region [6,7,16], with a network of optical cavities in the 10 −4 -10 −1 Hz region [11], and using atomic spectroscopy in the 10 5 -10 8 Hz region [17]. This has also given rise to various proposals for experiments to further extend the frequency range of searches for oscillations in the constants of nature: using a future atomic gravitational waves detector in the 10 −3 -10 3 Hz region [18], using future resonnant-mass detectors in the 10 4 -10 6 Hz region [19], using a laser gravitational waves detector in the 10 −2 -10 2 Hz region [20][21][22], etc.…”