Itinerant quantum critical point with frustration and non-Fermi-liquid

Understand

Employing the self-learning quantum Monte Carlo algorithm, we investigate the frustrated transverse-field triangle-lattice Ising model coupled to a Fermi surface.

• Without fermions, the spin degrees of freedom undergoes a second-order quantum phase transition between paramagnetic and clock-ordered phases.
• This quantum critical point (QCP) has an emergent U(1) symmetry and thus belongs to the (2+1)D XY universality class.
• In the presence of fermions, spin fluctuations introduce effective interactions among fermions and distort the bare Fermi surface towards an interacting one with hot spots and Fermi pockets.