Optical Pumping of TeH+: Implications for the Search for Varying mp/me

TL;DR

This paper explores laser cooling techniques for TeH+ molecules to enhance precision in detecting variations in the proton-to-electron mass ratio, which could improve current limits on fundamental constant variations.

Contribution

It introduces broadband laser cooling schemes for TeH+ and evaluates their potential to improve sensitivity to $mma$ variations.

Findings

Laser cooling of TeH+ is feasible with broadband lasers.

Simulations show potential for significant sensitivity improvements.

TeH+ can be effectively prepared for high-precision measurements.

Abstract

Molecular overtone transitions provide optical frequency transitions sensitive to variation in the proton-to-electron mass ratio ($\mu\equiv m_p/m_e$). However, robust molecular state preparation presents a challenge critical for achieving high precision. Here, we characterize infrared and optical-frequency broadband laser cooling schemes for TeH$^+$, a species with multiple electronic transitions amenable to sustained laser control. Using rate equations to simulate laser cooling population dynamics, we estimate the fractional sensitivity to $\mu$ attainable using TeH$^+$. We find that laser cooling of TeH$^+$ can lead to significant improvements on current $\mu$ variation limits.