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Marco G. Tarallo

Publications and source records attributed to Marco G. Tarallo.

6 recordsLinked to original sources

Quantum Monte Carlo study of the role of p-wave interactions in ultracold repulsive Fermi gases

Single-component ultracold atomic Fermi gases are usually described using noninteracting many-fermion models. However, recent experiments reached a regime where $p$-wave interactions among identical fermionic atoms are important. In this paper, we employ variational and fixed-node diffusion Monte Carlo simulations to investigate the ground-state properties of single-component Fermi gases with short-range repulsive interactions. We determine the zero-temperature equation of state, and elucidate the roles played by the $p$-wave scattering volume and the $p$-wave effective range. A comparison against recently derived second-order perturbative results shows good agreement in a broad range of interaction strength. We also compute the quasiparticle effective mass, and we confirm the perturbative prediction of a linear contribution in the $p$-wave scattering volume, while we find significant deviations from the beyond-mean-field perturbative result, already for moderate interaction strengths. Finally, we determine ground-state energies for two-component unpolarized Fermi gases with both interspecies and intraspecies hard-sphere interactions, finding remarkable agreement with a recently derived fourth-order expansion that includes $p$-wave contributions.

cond-mat.quant-gas

One-Dimensional Disordered Bosonic Systems

Disorder is everywhere in nature and it has a fundamental impact on the behavior of many quantum systems. The presence of a small amount of disorder, in fact, can dramatically change the coherence and transport properties of a system. Despite the growing interest in this topic, a complete understanding of the issue is still missing. An open question, for example, is the description of the interplay of disorder and interactions, which has been predicted to give rise to exotic states of matter such as quantum glasses or many-body localization. In this review, we will present an overview of experimental observations with disordered quantum gases, focused on one-dimensional bosons, and we will connect them with theoretical predictions.

cond-mat.dis-nn

Optically loaded Strontium lattice clock with a single multi-wavelength reference cavity

We report on the realization of a new compact strontium optical clock using a 2-D magneto-optical-trap (2D-MOT) as cold atomic source and a multi-wavelength cavity as the frequency stabilization system. All needed optical frequencies are stabilized to a zero-thermal expansion high-finesse optical resonator and can be operated without frequency adjustments for weeks. We present the complete characterization of the apparatus. Optical control of the atomic source allows us to perform low-noise clock operation without atomic signal normalization. Long- and short-term stability tests of the clock have been performed for the 88 Sr bosonic isotope by means of interleaved clock operation. Finally, we present the first preliminary accuracy budget of the system.

physics.atom-ph

Toward a quantum-enhanced strontium optical lattice clock at INRIM

The new strontium atomic clock at INRIM seeks to establish a new frontier in quantum measurement by joining state-of-the-art optical lattice clocks and the quantized electromagnetic field provided by a cavity QED setup. The goal of our experiment is to apply advanced quantum techniques to state-of-the-art optical lattice clocks, demonstrating enhanced sensitivity while preserving long coherence times and the highest accuracy. In this paper we describe the current status of the experiment and the prospected sensitivity gain for the designed cavity QED setup.

physics.atom-ph

A Sideband-Enhanced Cold Atomic Source For Optical Clocks

We demonstrate the enhancement and optimization of a cold strontium atomic beam from a two-dimensional magneto-optical trap (2D-MOT) transversely loaded from a collimated atomic beam by adding a sideband frequency to the cooling laser. The parameters of the cooling and sideband beams were scanned to achieve the maximum atomic beam flux and compared with Monte Carlo simulations. We obtained a 2.3 times larger, and 4 times brighter, atomic flux than a conventional, single-frequency 2D-MOT, for a given total power of 200 mW. We show that the sideband-enhanced 2D-MOT can reach the loading rate performances of space demanding Zeeman slower-based systems, while it can overcome systematic effects due to thermal beam collisions and hot black-body radiation shift, making it suitable for both transportable and accurate optical lattice clocks. Finally we numerically studied the possible extensions of the sideband-enhanced 2D-MOT to other alkaline-earth species.

physics.atom-ph