Browsing by Author "Astrakharchik, Grigori"

AndreevBashkin effect in superfluid cold gases mixtures
Nespolo, Jacopo; Astrakharchik, Grigori; Recati, Alessio (20171205)
Article
Open Access© 2017 The Author(s). Published by IOP Publishing Ltd on behalf of Deutsche Physikalische Gesellschaft. We study a mixture of two superfluids with densitydensity and currentcurrent (AndreevBashkin) interspecies interactions. ... 
Bose polarons in ultracold atoms in one dimension: beyond the Fröhlich paradigm
Grusdt, Fabian; Astrakharchik, Grigori; Demler, Eugene (20171025)
Article
Open AccessMobile impurity atoms immersed in Bose–Einstein condensates provide a new platform for exploring Bose polarons. Recent experimental advances in the field of ultracold atoms make it possible to realize such systems with ... 
Coherent oscillations in small Fermipolaron systems
Tylutki, Marek; Astrakharchik, Grigori; Recati, Alessio (AMER PHYSICAL SOC, 20171201)
Article
Open AccessWe study the ground state and excitations of a onedimensional trapped polarized Fermi gas interacting with a single impurity. First, we study the tunneling dynamics of the impurity through a potential barrier, such as one ... 
Composite boson description of a lowdensity gas of excitons
Golomedov, A. E.; Lozovik, Yu. E.; Astrakharchik, Grigori; Boronat Medico, Jordi (20171013)
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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 ... 
Distinguishability, degeneracy, and correlations in three harmonically trapped bosons in one dimension
Garcia March, Miguel Angel; Julia Diaz, Bruno; Astrakharchik, Grigori; Boronat Medico, Jordi; Polls, A. (20141201)
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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 ... 
Dynamics of onedimensional quantum droplets
Astrakharchik, Grigori; Malomed, Boris A. (American Physical Society (APS), 20180730)
Article
Open AccessThe structure and dynamics of onedimensional binary Bose gases forming quantum droplets is studied by solving the corresponding amended GrossPitaevskii equation. Two physically different regimes are identified, corresponding ... 
Dynamic structure function of a cold Fermi gas at unitarity
Astrakharchik, Grigori; Boronat Medico, Jordi; Krotscheck, Eckhard; Lichtenegger, Thomas (Institute of Physics (IOP), 20140814)
Article
Open AccessWe present a theoretical study of the dynamic structure function of a resonantly interacting twocomponent Fermi gas at zero temperature. Our approach is based on dynamic manybody theory able to describe excitations in ... 
Exact groundstate properties of a onedimensional Coulomb gas
Astrakharchik, Grigori; Girardeau, M.D. (20110415)
Article
Open AccessThe groundstate properties of a singlecomponent onedimensional Coulomb gas are investigated. We use BoseFermi mapping for the groundstate wave function which permits solution of the Fermi sign problem in the following ... 
Gapped spectrum in pairsuperfluid bosons
Astrakharchik, Grigori; Zillich, Robert E.; Mazzanti Castrillejo, Fernando Pablo; Boronat Medico, Jordi (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 ... 
Lowdimensional weakly interacting Bose gases: nonuniversal equations of state
Astrakharchik, Grigori; Boronat Medico, Jordi; Kurbakov, I L; Lozovik, Y E; Mazzanti Castrillejo, Fernando Pablo (201001)
Article
Open AccessThe zerotemperature equation of state is analyzed in lowdimensional bosonic systems. We propose to use the concept of energydependent swave scattering length for obtaining estimations of nonuniversal terms in the energy ... 
Luttingerliquid behavior of onedimensional He3
Astrakharchik, Grigori; Boronat Medico, Jordi (20141230)
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Open AccessThe groundstate properties of onedimensional He3 are studied using quantum Monte Carlo methods. The equation of state is calculated in a wide range of physically relevant densities and is well interpolated by a powerseries ... 
Onedimensional Bose gas in optical lattices of arbitrary strength
Astrakharchik, Grigori; Krutitsky, K.V.; Lewenstein, Maciej; Mazzanti Castrillejo, Fernando Pablo (20160208)
Article
Open AccessOnedimensional Bose gas with contact interaction in optical lattices at zero temperature is investigated by means of the exact diffusion Monte Carlo algorithm. The results obtained from the fundamental continuous model ... 
One dimensional H1, H2 and H3
Vidal, A.J.; Astrakharchik, Grigori; Vranješ Markic, Leandra; Boronat, J. (20160526)
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Open AccessThe groundstate properties of onedimensional electronspinpolarized hydrogen H1, deuterium H2, and tritium 3 Hare obtained by means of quantum Monte Carlo methods. The equations of state of the three isotopes are ... 
Onedimensional multicomponent Fermi gas in a trap: quantum Monte Carlo study
Matveeva, N.; Astrakharchik, Grigori (20160622)
Article
Open AccessA onedimensional world is very unusual as there is an interplay between quantum statistics and geometry, and a strong shortrange repulsion between atoms mimics Fermi exclusion principle, fermionizing the system. Instead, ... 
Onedimensional threeboson problem with two and threebody interactions
Guijarro Gámez, Grecia; Pricoupenko, A.; Astrakharchik, Grigori; Boronat Medico, Jordi; Petrov, D. S. (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, ... 
Optical lattices as a tool to study defectinduced superfluidity
Astrakharchik, Grigori; Krutitsky, K.V.; Lewenstein, Maciej; Mazzanti Castrillejo, Fernando Pablo; Boronat Medico, Jordi (AMER PHYSICAL SOC, 20170905)
Article
Open AccessWe study the superfluid response, the energetic and structural properties of a onedimensional ultracold Bose gas in an optical lattice of arbitrary strength. We use the BoseFermi mapping in the limit of infinitely large ... 
Phase diagram of a quantum Coulomb wire
Ferré Porta, Guillem; Astrakharchik, Grigori; Boronat Medico, Jordi (20151209)
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Open Access 
Phase diagram of quasitwodimensional bosons in a laserspeckle potential
Astrakharchik, Grigori; Krutitsky, K.V.; Navez, Patrick (201306)
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Open AccessWe have studied the phase diagram of a quasitwodimensional interacting Bose gas at zero temperature in the presence of random potential created by laser speckles. The superfluid fraction and the fraction of particles ... 
Quantum correlations and spatial localization in onedimensional ultracold bosonic mixtures
Garcia March, Miguel Angel; Julia Diaz, Bruno; Astrakharchik, Grigori; Busch, Th; Boronat Medico, Jordi; Polls, A. (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, ... 
Quantum phase transition with a simple variational ansatz
Lutsyshyn, Yaroslav; Astrakharchik, Grigori; Cazorla, C; Boronat Medico, Jordi (20141211)
Article
Open AccessWe study the zerotemperature quantum phase transition between liquid and hcp solid He4. We use the variational method with a simple yet exchangesymmetric and fully explicit wave function. It is found that the optimized ...