2025/06/04 by Crawford, Zachary, Goga, Adam, Kovtun, Mikael +1
#Computational Physics (physics.comp-ph) #Disordered Systems and Neural Networks (cond-mat.dis-nn) #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
paper · doi:10.48550/arxiv.2506.03676
Due to recent advances, silicon solar cells are rapidly approaching the Shockley-Queisser limit of 33% efficiency. Quantum Dot (QD) solar cells have the potential to surpass this limit and enable a new generation of photovoltaic technologies beyond the capabilities of any existing solar energy modalities. The creation of the first epitaxially-fused quantum dot solids showing broad phase coherence and metallicity necessary for solar implementation has not yet been achieved, and the metal-insulator transition in these materials needs to be explored. We have created a new model of electron transport through QD solids, informed by 3D-tomography of QD solid samples, which considers disorder in both the on-site and hopping terms of the commonly studied Anderson Hamiltonian. We used the transfer matrix method and finite-size scaling to create a dynamic metal-insulator transition phase diagram. For a surprisingly large portion of the parameter space, our model shows a critical exponent distinct from the expected value for the Anderson transition. We show the existence of a crossover region from the universality class of the Anderson transition (AI) to the Chiral Orthogonal class (BDI) due to the addition of weak kinetic (hopping) disorder.