Now showing items 1-18 of 18

• #### Beyond-Luttinger-liquid thermodynamics of a one-dimensional Bose gas with repulsive contact interactions ﻿

(American Physical Society, 2019-11-07)
Article
Open Access
We present a thorough study of the thermodynamics of a one-dimensional repulsive Bose gas, focusing in particular on corrections beyond the Luttinger-liquid description. We compute the chemical potential, pressure, and ...
• #### Bose-Bose mixtures at finite temperature ﻿

(Universitat Politècnica de Catalunya, 2019-06-25)
Bachelor thesis
Restricted access - author's decision
• #### Composite boson description of a low-density gas of excitons ﻿

(2017-10-13)
Article
Open Access
Ground-state properties of a fermionic Coulomb gas are calculated using the fixed-node diffusion Monte Carlo method. The validity of the composite boson description is tested for different densities. We extract the ...
• #### Diffusion Monte Carlo methods for spin-orbit-coupled ultracold Bose gases ﻿

(American Physical Society (APS), 2018-11-27)
Article
Open Access
We present two diffusion Monte Carlo (DMC) algorithms for systems of ultracold quantum gases featuring synthetic spin-orbit interactions. The first one is a spin-integrated DMC method which provides fixed-phase energy ...
• #### Dipolar Bose Supersolid Stripes ﻿

(2017-12-20)
Article
Open Access
We study the superfluid properties of a system of fully polarized dipolar bosons moving in the XY plane. We focus on the general case where the polarization field forms an arbitrary angle a with respect to the Z axis, ...
• #### Distinguishability, degeneracy, and correlations in three harmonically trapped bosons in one dimension ﻿

(2014-12-01)
Article
Open Access
We study a system of two bosons of one species and a third atom of a second species in a one-dimensional parabolic trap at zero temperature. We assume contact repulsive inter- and intraspecies interactions. By means of an ...
• #### Droplets of trapped quantum dipolar bosons ﻿

(2016-11-10)
Article
Open Access
Strongly interacting systems of dipolar bosons in three dimensions confined by harmonic traps are analyzed using the exact path integral ground-state Monte Carlo method. By adding a repulsive two-body potential, we find a ...
• #### Effects of Fermion Exchange on the Polarization of Exciton Condensates ﻿

(APS Physics, 2015-03-04)
Article
Open Access
Exchange interaction is responsible for the stability of elementary boson condensates with respect to momentum fragmentation. This remains true for composite bosons when single fermion exchanges are included but spin ...
• #### Few-body bound states of two-dimensional bosons ﻿

(American Physical Society (APS), 2020-04-07)
Article
Open Access
We study clusters of the type $A_NB_M$ with N=M=3 in a two-dimensional mixture of A and B bosons, with attractive AB and equally repulsive AA and BB interactions. In order to check universal aspects of the problem, we ...
• #### Gapped spectrum in pair-superfluid bosons ﻿

(2016-12-22)
Article
Open Access
We study the ground state of a bilayer system of dipolar bosons with dipoles oriented by an external field perpendicularly to the two parallel planes. By decreasing the interlayer distance, for a fixed value of the strength ...
• #### One dimensional quantum gases: from few to many ﻿

(Universitat Politècnica de Catalunya, 2016-07-07)
Bachelor thesis
Open Access
Covenantee:   Università degli studi di Trento
The main objective of this project is to find the binding energy of an impurity interacting with a one-dimensional bosonic system of increasing size for different coupling strengths g. Both the bosons as well as the impurity ...
• #### One-dimensional three-boson problem with two- and three-body interactions ﻿

(American Physical Society (APS), 2018-06-14)
Article
Open Access
We solve the three-boson problem with contact two- and three-body interactions in one dimension and analytically calculate the ground and excited trimer-state energies. Then, by using the diffusion Monte Carlo technique, ...
• #### Phase diagram of dipolar bosons in two dimensions with tilted polarization ﻿

(2014-12-01)
Article
Open Access
We analyze the ground state of a system of dipolar bosons moving in the XY plane and such that their dipolar moments are all aligned in a fixed direction in space. We focus on the general case where the polarization field ...
• #### Quantum correlations and spatial localization in one-dimensional ultracold bosonic mixtures ﻿

(2014-10-07)
Article
Open Access
We present the complete phase diagram for one-dimensional binary mixtures of bosonic ultracold atomic gases in a harmonic trap. We obtain exact results with direct numerical diagonalization for a small number of atoms, ...
• #### Reentrant behavior of the breathing-mode-oscillation frequency in a one-dimensional Bose gas ﻿

(2015-08-07)
Article
Open Access
Exciting temporal oscillations of the density distribution is a high-precision method for probing ultracold trapped atomic gases. Interaction effects in their many-body dynamics are particularly puzzling and counter-intuitive ...
• #### Single-particle versus pair superfluidity in a bilayer system of dipolar bosons ﻿

(2014-10-21)
Article
Open Access
We consider the ground state of a bilayer system of dipolar bosons, where dipoles are oriented by an external field in the direction perpendicular to the parallel planes. Quantum Monte Carlo methods are used to calculate ...
• #### Vortex macroscopic superpositions in ultracold bosons in a double-well potential ﻿

(2015-03-23)
Article
Open Access
We study macroscopic superpositions in the orbital rather than the spatial degrees of freedom, in a three-dimensional double-well system. We show that the ensuing dynamics of N interacting excited ultracold bosons, which ...
• #### Zero-temperature phase diagram of Yukawa bosons ﻿

(2012)
Article
Open Access
We study the zero-temperature phase diagram of bosons interacting via screened Coulomb (Yukawa) potential by means of the diffusion Monte Carlo method. The Yukawa potential is used as a model interaction in the neutron ...