Related papers: Contact interaction in an unitary ultracold Fermi …
The Unitary Fermi Gas (UFG) is one of the most strongly interacting systems known to date, as it saturates the unitarity bound on the quantum mechanical scattering cross section. The UFG corresponds to a two-component Fermi gas in the limit…
A quantity known as the contact plays a fundamental role in quantum many-body systems with short-range interactions. The determination of the temperature dependence of the contact for the unitary Fermi gas of infinite scattering length has…
An ultracold Fermi gas with a zero-range attractive potential in the unitary limit is investigated using variational and diffusion Monte Carlo methods. Previous calculations have used a finite range interactions and extrapolate the results…
The recently discovered universal thermodynamic behaviour of dilute, strongly interacting Fermi gases also implies a universal structure in the many-body pair-correlation function at short distances, as quantified by the contact ${\cal I}$.…
The contact parameter in unitary Fermi Gases governs the short-distance, high-momentum, and high-energy properties of the system. We perform accurate quantum Monte Carlo calculations with highly optimized trial functions to precisely…
In recent years Quantum Monte Carlo techniques provided to be a valuable tool to study strongly interacting Fermi gases at zero temperature. We have used QMC methods to investigate several properties of the two-components Fermi gas at…
A key quantity in strongly-interacting resonant Fermi gases is the contact $\mathcal{C}$, which characterizes numerous properties such as the momentum distribution at large momenta or the pair correlation function at short distances. The…
We present a high-precision determination of the universal contact parameter in a strongly interacting Fermi gas. In a trapped gas at unitarity we find the contact to be $3.06 \pm 0.08$ at a temperature of 0.08 of the Fermi temperature in a…
The physics of quantum degenerate Fermi gases in uniform as well as in harmonically trapped configurations is reviewed from a theoretical perspective. Emphasis is given to the effect of interactions which play a crucial role, bringing the…
We revisit the properties of the two-component Fermi gas with short-range interactions in three dimensions, in the limit where the s-wave scattering length diverges. Such a unitary Fermi gas possesses universal thermodynamic and dynamical…
Variational and diffusion quantum Monte Carlo (VMC and DMC) calculations of the properties of the zero-temperature fermionic gas at unitarity are reported. The ratio of the energy of the interacting to the non-interacting gas for a system…
The contact ${\cal I}$, introduced by Tan, has emerged as a key parameter characterizing universal properties of strongly interacting Fermi gases. For ultracold Fermi gases near a Feshbach resonance, the contact depends upon two quantities:…
From sand piles to electrons in metals, one of the greatest challenges in modern physics is to understand the behavior of an ensemble of strongly interacting particles. A class of quantum many-body systems such as neutron matter and cold…
Quantum Monte Carlo techniques are employed to study the properties of polarons in an ultracold Fermi gas, at $T= 0,$ and in the unitary regime using both a zero-range model and a square-well potential. For a fixed density, the potential…
The ultra-cold and weakly-coupled Fermi gas in two spatial dimensions is studied in an effective field theory framework. It has long been observed that universal corrections to the energy density to two orders in the interaction strength do…
We study the relationship between Tan's contact parameter and the macroscopic dynamic properties of an ultracold trapped gas, such as the frequencies of the collective oscillations and the propagation of sound in one-dimensional (1D)…
We develop a theoretical method going beyond the contact-interaction approximation frequently used in mean-field theories of many-fermion systems, based on the low-energy T-matrix of the pair potential to rigorously define the effective…
We show, using an ab initio approach based on Quantum Monte Carlo technique, that the pseudogap regime emerges in ultracold Fermi gases close to the unitary point. We locate the onset of this regime at a value of the interaction strength…
Ultracold atomic gases with short-range interactions are characterized by a number of universal species-independent relations. Many of these relations involve the two-body Tan contact. Employing the canonical ensemble, we determine the Tan…
Ultracold atomic gases have proven to be remarkable model systems for exploring quantum mechanical phenomena. Experimental work on gases of fermionic atoms in particular has seen large recent progress including the attainment of so-called…