The department of telecommunications (DoT) is working on freeing up more spectrum for 5G services that could be auctioned in the next financial year starting April 1. Officials aware of the details told ET that along with mid-band spectrum (1 GHz to 6 GHz), DoT is also looking at the sub-6 GHz bands or the milli-meter wave band (mmWave), particularly between 37 GHz and 42 GHz, for the next-gen services.