Quantum Monte Carlo simulations of thermodynamic properties of SU(2N) ultracold fermions in optical lattices

We have systematically studied the thermodynamic properties of a two-dimensional half-filled SU(2N ) Hubbard model on a square lattice by using the determinant quantum Monte Carlo method. The entropytemperature relation, the isoentropy curve, and the probability distribution of the on-site occupation number are calculated in both SU(4) and SU(6) cases, which exhibit prominent features of the Pomeranchuk effect. We analyze these thermodynamic behaviors based on energy scales in the density and spin channels. In the density channel, the interaction strength that marks the crossover from the weak to strong interaction regimes increases with the number of fermion components. In the spin channel, increasing the number of fermion components enhances quantum spin fluctuations, which is shown in the simulations of uniform spin susceptibilities and antiferromagnetic structure factors.