Density Shift of Optical Lattice Clock via Multi-Bands Sampling Exact Diagonalization Method

TL;DR

This paper introduces a novel numerical algorithm called MBSED that accurately calculates the density shift in optical lattice clocks by considering multi-band atomic collisions, improving precision over previous models.

Contribution

The paper presents the MBSED algorithm, combining Monte Carlo sampling and exact diagonalization, to analyze density shifts at higher temperatures with greater accuracy.

Findings

Density shift of Rabi spectrum is slightly non-linear with atom number.

MBSED provides higher precision in density shift calculations.

The method can be applied to other quantum metrology platforms.

Abstract

Density shift plays one of the major roles in the uncertainty of optical lattice clock, thus has attracted lots of theoretical and experimental studies. However, most of the theoretical research considered the single-band and collective approximation, so the density shift of the system at higher temperatures can not be analyzed accurately. Here, we design a numerical algorithm that combines Monte Carlo sampling and exact diagonalization and name it as Multi-Band Sampling Exact Diagonalization (MBSED). The MBSED method considers the collision of atoms between multi-bands, so it can provide the density shift of an optical lattice clock with higher precision. Such an algorithm will benefit the numerical simulation of an optical lattice clock, and may also be used in other platforms of quantum metrology. In addition, through our numerical simulation, we also found that the density shift of Rabi spectrum is slightly non-linear with atom number.