Quantum-dot lithium in zero magnetic field: Electronic properties, thermodynamics, and Fermi liquid-Wigner solid crossover in the ground state

Energy spectra, electron densities, pair-correlation functions, and heat capacity of quantum-dot lithium in zero external magnetic field (a system of three interacting two-dimensional electrons in a parabolic confinement potential! are studied using the exact diagonalization approach. Particular attention is given to a Fermi liquid-Wigner solid crossover in the ground state of the dot, induced by intradot Coulomb interaction.