Characterizing the fundamental bending vibration of a linear polyatomic molecule for symmetry violation searches
Arian Jadbabaie, Yuiki Takahashi, Nickolas Pilgram, Chandler J. Conn, Yi Zeng, Chi Zhang, Nicholas R. Hutzler
Abstract
Abstract Polyatomic molecules have been identified as sensitive probes of charge-parity violating and parity violating physics beyond the Standard Model (BSM). For example, many linear triatomic molecules are both laser-coolable and have parity doublets in the ground electronic <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mi>X</mml:mi> <mml:mo stretchy="false">˜</mml:mo> </mml:mover> <mml:msup> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msup> <mml:msup> <mml:mi mathvariant="normal">Σ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>010</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> state arising from the bending vibration, both features that can greatly aid BSM searches. Understanding the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mi>X</mml:mi> <mml:mo stretchy="false">˜</mml:mo> </mml:mover> <mml:msup> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msup> <mml:msup> <mml:mi mathvariant="normal">Σ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>010</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> state is a crucial prerequisite to precision measurements with linear polyatomic molecules. Here, we characterize the fundamental bending vibration of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow/> <mml:mrow> <mml:mn>174</mml:mn> </mml:mrow> </mml:msup> </mml:math> YbOH using high-resolution optical spectroscopy on the nominally forbidden <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mi>X</mml:mi> <mml:mo stretchy="false">˜</mml:mo> </mml:mover> <mml:msup> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msup> <mml:msup> <mml:mi mathvariant="normal">Σ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>010</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow/> <mml:mo stretchy="false">→</mml:mo> <mml:mrow/> <mml:mover> <mml:mi>A</mml:mi> <mml:mo stretchy="false">˜</mml:mo> </mml:mover> <mml:msup> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msup> <mml:msub> <mml:mi mathvariant="normal">Π</mml:mi> <mml:mrow> <mml:mn>1</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:mo stretchy="false">(</mml:mo> <mml:mn>000</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> transition at 588 nm. We assign 39 transitions originating from the lowest rotational levels of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mi>X</mml:mi> <mml:mo stretchy="false">˜</mml:mo> </mml:mover> <mml:msup> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msup> <mml:msup> <mml:mi mathvariant="normal">Σ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>010</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> state, and accurately model the state’s structure with an effective Hamiltonian using best-fit parameters. Additionally, we perform Stark and Zeeman spectroscopy on the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mi>X</mml:mi> <mml:mo stretchy="false">˜</mml:mo> </mml:mover> <mml:msup> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msup> <mml:msup> <mml:mi mathvariant="normal">Σ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>010</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> state and fit the molecule-frame dipole moment to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mi>D</mml:mi> <mml:mrow> <mml:mi mathvariant="normal">m</mml:mi> <mml:mi mathvariant="normal">o</mml:mi> <mml:mi mathvariant="normal">l</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:mn>2.16</mml:mn> <mml:mo stretchy="false">(</mml:mo> <mml:mn>1</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> D and the effective electron g -factor to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mi>g</mml:mi> <mml:mi>S</mml:mi> </mml:msub> <mml:mo>=</mml:mo> <mml:mn>2.07</mml:mn> <mml:mo stretchy="false">(</mml:mo> <mml:mn>2</mml:mn>