The PhD student of the week: Ilirjan Aliaj

Ilirjan Aliaj
I am doing a PhD in physics at the SNS. Before that, I completed my Bachelor and Master’s Degree at the University of Pisa and continued my Master thesis project at NEST with a research fellow contract with SNS.
My PhD project focuses on correlated electronic phases driven by strong Coulomb interactions between closely spaced double layers of 2-dimensional electron/hole gases (2DE/HG); Bose-Einstein condensation of interlayer excitons is expected in suitable conditions. I realize these coupled bilayers by transferring graphene on top of either GaAs/AlGaAs or LaAlO3/SrTiO3 (LAO/STO) heterostructures, each of the latter hosting a shallow 2DEG. My ultimate goal is to fabricate devices where both the graphene and the 2DEG are gate-tunable and independently contacted; the interlayer correlations could then be probed by Coulomb drag measurements. I explored the vertical graphene – LAO/STO electrical transport at room temperature, and I found it to be highly non-linear; furthermore the LAO/STO 2DEG is extremely efficient in tuning the graphene chemical potential across the Dirac point. Both these effects are heavily influenced by the graphene quantum capacitance and they offer novel device applications.