The blackbody radiation vibrational level shifts in the ground electronic state of N$_{2}^{+}$

TL;DR

This paper uses ab-initio calculations to determine blackbody radiation-induced vibrational level shifts in N₂⁺, aiding the development of molecular frequency standards and tests for fundamental physics.

Contribution

It provides the first detailed quantum chemical analysis of BBR shifts in N₂⁺ vibrational levels, crucial for precision measurements and fundamental constant variation searches.

Findings

Calculated potential energy curve and polarizability tensor for N₂⁺ ground state.

Quantified BBR shifts for vibrational levels, enabling more accurate experimental setups.

Supports the use of N₂⁺ in frequency standards and fundamental physics tests.

Abstract

Homonuclear molecules have emerged as a crucial component in the pursuit of frequency standards, offering a promising avenue for the discovery of new physics phenomena that transcend the standard model. They also provide a unique approach to constraining variations in fundamental constants over time, thereby complementing the capabilities of atomic clocks. A notable challenge faced by molecular and single atomic quantum systems is the management of blackbody radiation (BBR), which introduces significant systematic errors and is challenging to regulate effectively. To address this issue, we perform {\it ab-initio} quantum chemical calculations to accurately determine the potential energy curve and the polarizability tensor for the ground state of the N$_2^+$ molecular ion, one of the most promising candidates for searching for variation of $m_{e}/m_{p}$ and creating frequency standards. We then calculate the BBR shifts affecting the vibrational levels of the ground electronic X$^2\Sigma_g^+$ state, marking a substantial contribution towards the precise experimental measurements.