Revisiting the $J_1$-$J_2$ Heisenberg Model on a Triangular Lattice: Quasidegenerate Ground States and Phase Competition

It is generally believed that the spin-$\tfrac{1}{2}$ triangular-lattice $J_1$-$J_2$ Heisenberg model hosts a quantum spin liquid in the intermediate regime between the $120^\circ$ and stripe ordered phases. Density matrix renormalization group studies on cylinders have consistently found two nearly