Practical Limits for Large-Momentum-Transfer Clock Atom Interferometers

Atom interferometry on optical clock transitions is being pursued for numerous long-baseline exper-iments both terrestrially and for future space missions. Crucial to meeting the required sensitivities of these experiments is the implementation of large momentum transfer (> 103hk). Here, we show that to sequentially apply such a large momentum via pi pulses places stringent requirements on the frequency noise of the interferometry laser and we find that the linewidth is required to be considerably lower than the previous estimate of approximately 10 Hz. This is due to imperfect pulse fidelity in the presence of noise and is apparent even for an atom at rest interacting with resonant light, making this a fundamen-tal constraint on operational fidelity for a given laser and pulse sequence. Within this framework, we further present and analyze two high-power frequency-stabilized laser sources designed to perform inter-ferometry on the 1S0-3P0 clock transitions of cadmium and strontium, operating at 332 nm and 698 nm, respectively.