Babadi, MehrtashSkinner, BrianFogler, Michael M.Demler, Eugene2014-11-242013Babadi, Mehrtash, Brian Skinner, Michael M. Fogler, and Eugene Demler. 2013. “Universal Behavior of Repulsive Two-Dimensional Fermions in the Vicinity of the Quantum Freezing Point.” EPL (Europhysics Letters) 103 (1) (July 1): 16002. doi:10.1209/0295-5075/103/16002.0295-50751286-4854http://nrs.harvard.edu/urn-3:HUL.InstRepos:13421144We show by a meta-analysis of the available Quantum Monte Carlo (QMC) results that two-dimensional fermions with repulsive interactions exhibit universal behavior in the strongly correlated regime, and that their freezing transition can be described using a quantum generalization of the classical Hansen-Verlet freezing criterion. We calculate the liquid-state energy and the freezing point of the 2D dipolar Fermi gas (2DDFG) using a variational method by taking ground-state wave functions of 2D electron gas (2DEG) as trial states. A comparison with the recent fixed-node diffusion Monte Carlo analysis of the 2DDFG shows that our simple variational technique captures more than 95% of the correlation energy, and predicts the freezing transition within the uncertainty bounds of QMC. Finally, we utilize the ground-state wave functions of 2DDFG as trial states and provide a variational account of the effects of finite 2D confinement width. Our results indicate significant beyond mean-field effects. We calculate the frequency of collective monopole oscillations of the quasi-2D dipolar gas as an experimental demonstration of correlation effects.en-USCondensed matter: electrical, magnetic and opticalCondensed matter: structural, mechanical & thermalJournal Article2014-11-2410.1209/0295-5075/103/16002