  Double beta $\beta\beta$ decay experiments are one of the most active
research topics in Neutrino Physics. The measurement of the neutrinoless mode
$0\nu\beta\beta$ could give unique information on the neutrino mass scale and
nature. The current generation of experiments aims at detector target masses at
the 100 kg scale, while the next generation will need to go to the ton scale in
order to completely explore the inverse hierarchy models of neutrino mass. Very
good energy resolutions and ultra-low background levels are the two main
experimental requirements for a successful experiment. The topological
information of the $\beta\beta$ events offered by gaseous detectors like gas
Time Projection Chambers (TPC) could provide a very powerful tool of signal
identification and background rejection. However only recent advances in TPC
readouts may assure the competitiveness of a high pressure gas TPCs for
$\beta\beta$ searches, especially regarding the required energy resolution. In
this paper we present first results on energy resolution with state-of-the-art
microbulk Micromesh Gas Amplification Structure (Micromegas) using a 5.5 MeV
alpha source in high pressure pure xenon. Resolutions down to 2 % FWHM have
been achieved for pressures up to 5 bar. These results, together with their
recently measured radiopurity , prove that Micromegas readouts are not only a
viable option but a very competitive one for $\beta\beta$ searches.
