Protocol for Optically Pumping AlH${}^{+}$ to a Pure Quantum State

Abstract

We propose an optical pumping scheme to prepare trapped ${\mathrm{AlH}}^{+}$ molecules in a pure state, the stretched hyperfine state $|F=\frac{7}{2},m_F=\frac{7}{2}⟩$ of the rovibronic ground manifold $|{\mathrm{X}}^2{\Sigma }^{+},v=0,N=0⟩$. Our scheme utilizes linearly-polarized and circularly-polarized fields of a broadband pulsed laser to cool the rotational degree of freedom and drive the population to the hyperfine state, respectively. We simulate the population dynamics by solving a representative system of rate equations that accounts for the laser fields, blackbody radiation, and spontaneous emission. In order to model the hyperfine structure, new hyperfine constants of the ${\mathrm{A}}^2\Pi$ excited state were computed using a RASSCF wavefunction. We find that adding an infrared laser to drive the $1-0$ vibrational transition within the ${\mathrm{X}}^2{\Sigma }^{+}$ manifold accelerates the cooling process. The results show that under optimum conditions, the population in the target state of the rovibronic ground manifold can reach 63 $\%$ after 68 $\mu$s (330 ms) and 95 $\%$ after 25 ms (1.2 s) with (without) the infrared laser.

arXiv commentThis article is submitted to the Physical Chemical challenges for quantum information science/ quantum computing themed collection of PCCP. In this version, we added some details, modified the graphs and the descriptions that are suggested by the referees. We also fixed the problem of not displaying the affiliation correctly

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Cited by in corpus (2)

• Laser-coolable AcOH${}^{+}$ ion for $\mathcal{C}\mathcal{P}$-violation searches
• Features of Molecular Structure Beneficial for Optical Pumping