[8] One original problem with using gallium selenide in optics is that it is easily broken along cleavage lines and thus it can be hard to cut for practical application.

It has been found, however, that doping the crystals with indium greatly enhances their structural strength and makes their application much more practical.

Single layers of gallium selenide are dynamically stable two-dimensional semiconductors, in which the valence band has an inverted Mexican-hat shape, leading to a Lifshitz transition as the hole-doping is increased.

Several approaches have been developed to encapsulate GaSe mono- and few-layers, leading to improved chemical stability and electronic mobility.

After synthesis and cooling, the reaction vessel is opened and extraction of the GaSe nanoparticle solution is accomplished by addition of methanol.