Analysis and calibration of absorptive images of Bose-Einstein condensate at non-zero temperatures

TL;DR

This paper presents a method for accurately analyzing absorptive images of Bose-Einstein condensates at non-zero temperatures, reducing systematic errors and enabling precise calibration of the condensate and thermal fractions.

Contribution

The paper introduces a novel analysis technique that improves the quantitative interpretation and calibration of BEC images at finite temperatures.

Findings

Method reduces systematic errors in BEC image analysis.

Calibration of BEC and thermal fractions achieved with high precision.

Results agree well with theoretical models and independent measurements.

Abstract

We describe the method allowing quantitative interpretation of absorptive images of mixtures of BEC and thermal atoms which reduces possible systematic errors associated with evaluation of the contribution of each fraction. By using known temperature dependence of the BEC fraction, the analysis allows precise calibration of the fitting results. The developed method is verified in two different measurements and compares well with theoretical calculations and with measurements performed by another group.