Construction of an inexpensive molecular Iodine spectrometer using a self developed Pohl wavemeter around 670 nm wavelength

TL;DR

This paper presents a low-cost, easy-to-construct iodine spectrometer using a homemade vapor cell and a Pohl interferometer-based wavemeter at 670 nm, suitable for undergraduate physics experiments.

Contribution

It introduces a simple, inexpensive spectrometer design with a custom wavemeter and image processing, enabling atomic physics experiments in educational settings.

Findings

Resolution approaching 0.5 nm achieved

Easy construction with readily available components

Suitable for undergraduate teaching laboratories

Abstract

We describe construction of an inexpensive Iodine Spectrometer with a home made Iodine vapour cell and a self developed wavemeter based on Pohl Interferometer, around 670 nm wavelength.This can be easily realised in an undergraduate teaching laboratory to demonstrate use of a diode laser interferometry using a Pohl interferometer and measurement of wavelength using image processing techniques.Visible alternative to the IR diode lasers, 670 nm diode laser used here give chance to undergraduate students to perform comprehensive though illustrative atomic physics experiments including the Zeeman effect, the Hanle effect, Magneto Optic Rotation (MOR) effect with a little tweaking in the present spectrometer. The advantage of the spectrometer is its ease of construction with readily available optics, electronics, evacuation and glass blowing facilities and easy analysis algorithm to evaluate the wavelength. The self developed algorithm of raster scanning and circular averaging gives the researcher insight into the basics of image processing techniques. Resolution approaching 0.5 nm can be easily achieved using such simple setup.