ASEP / TASEP

Asymmetric Simple Exclusion Process — particles hop right with rate p, left with rate q, excluded from occupied sites. Shows KPZ universality class behavior.
HD Phase
High density: β limits exit
Phase boundary: α=β=0.5
LD: α < β, α < 0.5
HD: β < α, β < 0.5
MC: α > 0.5, β > 0.5
Current J = ρ(1-ρ)
MC current J = 1/4 (max)