Negative heat capacity in low-dimensional systems using non-local kernel approach

Thermodynamical systems having negative heat capacity are characterised by peculiar behaviours, yet they have been reported in several systems ranging from large to nanoscales. We show that negative heat capacity may arise in low-dimensional/nano quantum oscillators due to strong electron correlations observed in underdoped cuprates and quantum wells with negative density of states which emerge in several quantum systems including mesoscopic systems.