In 1928 he moved to the Dacca University (now in Bangladesh) as the Reader in the physics department where he studied magnetic properties of crystals in relation to their structure.

Guha, and Asutosh Mukherjee developed an elegant and precise experimental technique to measure the magnetic anisotropy of diamagnetic and paramagnetic crystals.

[4][5] In 1933 he returned to Kolkata to take up the post of Mahendralal Sircar Professor of Physics in the Indian Association for the Cultivation of Science where he continued to collaborate fruitfully with Banerjee to elaborate on the magnetic properties of crystals in relation to their structure.

Their experiments in Dacca and continued collaborative research in Kolkata led to what is now known as the Krishnan Banerjee method for measuring the magnetic susceptibility of small crystals.

More recently has been publishing many valuable investigations (Phil Trans Royal Society and elsewhere) on the significance of magnetic anisotropy in relation to crystal architecture and thermo-magnetic behaviour at the lowest temperatures.