Browsing by Subject "Bosons"
Now showing items 118 of 18

BeyondLuttingerliquid thermodynamics of a onedimensional Bose gas with repulsive contact interactions
(American Physical Society, 20191107)
Article
Open AccessWe present a thorough study of the thermodynamics of a onedimensional repulsive Bose gas, focusing in particular on corrections beyond the Luttingerliquid description. We compute the chemical potential, pressure, and ... 
BoseBose mixtures at finite temperature
(Universitat Politècnica de Catalunya, 20190625)
Bachelor thesis
Restricted access  author's decision 
Composite boson description of a lowdensity gas of excitons
(20171013)
Article
Open AccessGroundstate properties of a fermionic Coulomb gas are calculated using the fixednode diffusion Monte Carlo method. The validity of the composite boson description is tested for different densities. We extract the ... 
Diffusion Monte Carlo methods for spinorbitcoupled ultracold Bose gases
(American Physical Society (APS), 20181127)
Article
Open AccessWe present two diffusion Monte Carlo (DMC) algorithms for systems of ultracold quantum gases featuring synthetic spinorbit interactions. The first one is a spinintegrated DMC method which provides fixedphase energy ... 
Dipolar Bose Supersolid Stripes
(20171220)
Article
Open AccessWe 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
(20141201)
Article
Open AccessWe study a system of two bosons of one species and a third atom of a second species in a onedimensional parabolic trap at zero temperature. We assume contact repulsive inter and intraspecies interactions. By means of an ... 
Droplets of trapped quantum dipolar bosons
(20161110)
Article
Open AccessStrongly interacting systems of dipolar bosons in three dimensions confined by harmonic traps are analyzed using the exact path integral groundstate Monte Carlo method. By adding a repulsive twobody potential, we find a ... 
Effects of Fermion Exchange on the Polarization of Exciton Condensates
(APS Physics, 20150304)
Article
Open AccessExchange 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 ... 
Fewbody bound states of twodimensional bosons
(American Physical Society (APS), 20200407)
Article
Open AccessWe study clusters of the type $A_NB_M$ with N=M=3 in a twodimensional 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 pairsuperfluid bosons
(20161222)
Article
Open AccessWe 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, 20160707)
Bachelor thesis
Open Access
Covenantee: Università degli studi di TrentoThe main objective of this project is to find the binding energy of an impurity interacting with a onedimensional bosonic system of increasing size for different coupling strengths g. Both the bosons as well as the impurity ... 
Onedimensional threeboson problem with two and threebody interactions
(American Physical Society (APS), 20180614)
Article
Open AccessWe solve the threeboson problem with contact two and threebody interactions in one dimension and analytically calculate the ground and excited trimerstate energies. Then, by using the diffusion Monte Carlo technique, ... 
Phase diagram of dipolar bosons in two dimensions with tilted polarization
(20141201)
Article
Open AccessWe 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 onedimensional ultracold bosonic mixtures
(20141007)
Article
Open AccessWe present the complete phase diagram for onedimensional 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 breathingmodeoscillation frequency in a onedimensional Bose gas
(20150807)
Article
Open AccessExciting temporal oscillations of the density distribution is a highprecision method for probing ultracold trapped atomic gases. Interaction effects in their manybody dynamics are particularly puzzling and counterintuitive ... 
Singleparticle versus pair superfluidity in a bilayer system of dipolar bosons
(20141021)
Article
Open AccessWe 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 doublewell potential
(20150323)
Article
Open AccessWe study macroscopic superpositions in the orbital rather than the spatial degrees of freedom, in a threedimensional doublewell system. We show that the ensuing dynamics of N interacting excited ultracold bosons, which ... 
Zerotemperature phase diagram of Yukawa bosons
(2012)
Article
Open AccessWe study the zerotemperature 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 ...