We propose a theoretical framework,based on the two-component Gross-Pitaevskii equation(GPE),for the investigation of vortex solitons(VSs)in hybrid atomic-molecular Bose-Einstein condensates under the action of the st...We propose a theoretical framework,based on the two-component Gross-Pitaevskii equation(GPE),for the investigation of vortex solitons(VSs)in hybrid atomic-molecular Bose-Einstein condensates under the action of the stimulated Raman-induced photoassociation and square-optical-lattice potential.Stationary solutions of the coupled GPE system are obtained by means of the imaginary-time integration,while the temporal dynamics are simulated using the fourth-order Runge-Kutta algorithm.The analysis reveals stable rhombus-shaped VS shapes with topological charges m=1 and 2 of the atomic component.The stability domains and spatial structure of these VSs are governed by three key parameters:the parametric-coupling strength(χ),atomicmolecular interaction strength(g_(12)),and the optical-lattice potential depth(V_(0)).By varyingχand g_(12),we demonstrate a structural transition where four-core rhombus-shaped VSs evolve into eight-core square-shaped modes,highlighting the nontrivial nonlinear dynamics of the system.This work establishes a connection between interactions of cold atoms and topologically structured matter waves in hybrid quantum systems.展开更多
This concise review summarizes recent advancements in theoretical studies of vortex quantum droplets(VQDs)in matter-wave fields.These are robust self-trapped vortical states in two-and three-dimensional(2D and 3D)Bose...This concise review summarizes recent advancements in theoretical studies of vortex quantum droplets(VQDs)in matter-wave fields.These are robust self-trapped vortical states in two-and three-dimensional(2D and 3D)Bose–Einstein condensates(BECs)with intrinsic nonlinearity.Stability of VQDs is provided by additional nonlinearities resulting from quantum fluctuations around mean-field states,often referred to as the Lee–Huang–Yang(LHY)corrections.The basic models are presented,with emphasis on the interplay between the mean-field nonlinearity,LHY correction,and spatial dimension,which determines the structure and stability of VQDs.We embark by delineating fundamental properties of VQDs in the 3D free space,followed by consideration of their counterparts in the 2D setting.Additionally,we address stabilization of matter-wave VQDs by optical potentials.Finally,we summarize results for the study of VQDs in the single-component BEC of atoms carrying magnetic moments.In that case,the anisotropy of the long-range dipole-dipole interactions endows the VQDs with unique characteristics.The results produced by the theoretical studies in this area directly propose experiments for the observation of novel physical effects in the realm of quantum matter,and suggest potential applications to the design of new schemes for processing classical and quantum information.展开更多
Creation of stable self-trapped vortex states(alias vortex solitons)in Bose-Einstein condensates(BECs)in free space is a challenging problem[1].To date,an experimental demonstration of this possibility is missing.A ne...Creation of stable self-trapped vortex states(alias vortex solitons)in Bose-Einstein condensates(BECs)in free space is a challenging problem[1].To date,an experimental demonstration of this possibility is missing.A new powerful platform for the realization of various self-trapped states is offered by quantum droplets(QDs),i.e.,stable localized modes maintained by the balance of mean-field(MF)interactions and corrections to them induced by quantum fluctuations[2].Recent theoretical predictions[3,4]and experimental demonstrations[5-10]suggest various possibilities for the creation of novel fundamental and vortical patterns,as summarized in reviews[11-13].In particular,QDs with embedded vorticity were theoretically investigated in detail[14-21].展开更多
This item from the News and Views(N&V)category aims to provide a summary of theoretical and experimental results recently published in ref.24,which demonstrates the creation of corner modes in nonlinear optical wa...This item from the News and Views(N&V)category aims to provide a summary of theoretical and experimental results recently published in ref.24,which demonstrates the creation of corner modes in nonlinear optical waveguides of the higher-order topological insulator(HOTI)type.Actually,these are second-order HOTIs,in which the transverse dimension of the topologically protected edge modes is smaller than the bulk dimension(it is 2,in the case of optical waveguide)by 2,implying zero dimension of the protected modes,which are actually realized as corner or defect ones.Work24 reports the prediction and creation of various forms of the corner modes in a HOTI with a fractal transverse structure,represented by the Sierpiński gasket(SG).The self-focusing nonlinearity of the waveguide's material transforms the corner modes into corner solitons,almost all of which are stable.The solitons may be attached to external or internal corners created by the underlying SG.This N&V item offers an overview of these new findings reported in ref.24 and other recent works,and a brief discussion of directions for further work on this topic.展开更多
This brief review summarizes recent theoretical and experimental results which predict and establish the existence of quantum droplets(QDs),i.e.,robust two-and three-dimensional(2D and 3D)self-trapped states in Bose-E...This brief review summarizes recent theoretical and experimental results which predict and establish the existence of quantum droplets(QDs),i.e.,robust two-and three-dimensional(2D and 3D)self-trapped states in Bose-Einstein condensates(BECs),which are stabilized by effective self-repulsion induced by quantum fluctuations around the mean-field(MF)states[alias the Lee-Huang-Yang(LHY)effect].The basic models are presented,taking special care of the dimension crossover,2D→3D.Recently reported experimental results,which exhibit stable 3D and quasi-2D QDs in binary BECs,with the inter-component attraction slightly exceeding the MF self-repulsion in each component,and in single-component condensates of atoms carrying permanent magnetic moments,are presented in some detail.The summary of theoretical results is focused,chiefly,on 3D and quasi-2D QDs with embedded vorticity,as the possibility to stabilize such states is a remarkable prediction.Stable vortex states are presented both for QDs in free space,and for singular but physically relevant 2D modes pulled to the center by the inverse-square potential,with the quantum collapse suppressed by the LHY effect.展开更多
In the course of the past 25 years,several new quantum states of matter have been created in ultracold gases,starting from the celebrated Bose-Einstein condensates(BECs),which were first made in 1995,follow-ing the th...In the course of the past 25 years,several new quantum states of matter have been created in ultracold gases,starting from the celebrated Bose-Einstein condensates(BECs),which were first made in 1995,follow-ing the theoretical prediction published in 1924[1].This achievement was followed by the creation and detailed exploration of degenerate Fermi gases[2].展开更多
Creation of stable intrinsically anisotropic self-bound states with embedded vorticity is a challenging issue.Previously,no such states in Bose−Einstein condensates(BECs)or other physical settings were known.Dipolar B...Creation of stable intrinsically anisotropic self-bound states with embedded vorticity is a challenging issue.Previously,no such states in Bose−Einstein condensates(BECs)or other physical settings were known.Dipolar BEC suggests a unique possibility to predict stable two dimensional anisotropic vortex quantum droplets(2D-AVQDs).We demonstrate that they can be created with the vortex axis oriented perpendicular to the polarization of dipoles.The stability area and characteristics of the 2D-AVQDs in the parameter space are revealed by means of analytical and numerical methods.Further,the rotation of the polarizing magnetic field is considered,and the largest angular velocities,up to which spinning 2D-AVQDs can follow the rotation in clockwise and anti-clockwise directions,are found.Collisions between moving 2D-AVQDs are studied too,demonstrating formation of bound states with a vortex−antivortex−vortex structure.A stability domain for such stationary bound states is identified.Unstable dipolar states,that can be readily implemented by means of phase imprinting,quickly transform into robust 2D-AVQDs,which suggests a straightforward possibility for the creation of these states in the experiment.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.62275075)the Natural Science Foundation of Hubei Soliton Research Association(Grant No.2025HBSRA09)+1 种基金joint supported by Hubei Provincial Natural Science Foundation and Xianning of China(Grant Nos.2025AFD401 and 2025AFD405)Israel Science Foundation(Grant No.1695/22).
文摘We propose a theoretical framework,based on the two-component Gross-Pitaevskii equation(GPE),for the investigation of vortex solitons(VSs)in hybrid atomic-molecular Bose-Einstein condensates under the action of the stimulated Raman-induced photoassociation and square-optical-lattice potential.Stationary solutions of the coupled GPE system are obtained by means of the imaginary-time integration,while the temporal dynamics are simulated using the fourth-order Runge-Kutta algorithm.The analysis reveals stable rhombus-shaped VS shapes with topological charges m=1 and 2 of the atomic component.The stability domains and spatial structure of these VSs are governed by three key parameters:the parametric-coupling strength(χ),atomicmolecular interaction strength(g_(12)),and the optical-lattice potential depth(V_(0)).By varyingχand g_(12),we demonstrate a structural transition where four-core rhombus-shaped VSs evolve into eight-core square-shaped modes,highlighting the nontrivial nonlinear dynamics of the system.This work establishes a connection between interactions of cold atoms and topologically structured matter waves in hybrid quantum systems.
基金supported by Dongguan Science and Technology of Social Development Program (Grant No. 20231800940532)Songshan Lake Sci-Tech Commissioner Program (Grant No. 20234373–01KCJ-G)supported, in part, by the Israel Science Foundation (Grant No. 1695/22)
文摘This concise review summarizes recent advancements in theoretical studies of vortex quantum droplets(VQDs)in matter-wave fields.These are robust self-trapped vortical states in two-and three-dimensional(2D and 3D)Bose–Einstein condensates(BECs)with intrinsic nonlinearity.Stability of VQDs is provided by additional nonlinearities resulting from quantum fluctuations around mean-field states,often referred to as the Lee–Huang–Yang(LHY)corrections.The basic models are presented,with emphasis on the interplay between the mean-field nonlinearity,LHY correction,and spatial dimension,which determines the structure and stability of VQDs.We embark by delineating fundamental properties of VQDs in the 3D free space,followed by consideration of their counterparts in the 2D setting.Additionally,we address stabilization of matter-wave VQDs by optical potentials.Finally,we summarize results for the study of VQDs in the single-component BEC of atoms carrying magnetic moments.In that case,the anisotropy of the long-range dipole-dipole interactions endows the VQDs with unique characteristics.The results produced by the theoretical studies in this area directly propose experiments for the observation of novel physical effects in the realm of quantum matter,and suggest potential applications to the design of new schemes for processing classical and quantum information.
基金supported by the National Natural Science Foundation of China through Grant Nos.12274077,12475014,11874112,and 11905032the Natural Science Foundation of Guangdong Province through Grant Nos.2024A1515030131 and 2023A1515010770+2 种基金the Research Fund of Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology through Grant No.2020B1212030010supported,in part,by the Israel Science Foundation through Grant No.1695/2022research project FFUU-2024-0003 of the Institute of Spectroscopy of the Russian Academy of Sciences.
文摘Creation of stable self-trapped vortex states(alias vortex solitons)in Bose-Einstein condensates(BECs)in free space is a challenging problem[1].To date,an experimental demonstration of this possibility is missing.A new powerful platform for the realization of various self-trapped states is offered by quantum droplets(QDs),i.e.,stable localized modes maintained by the balance of mean-field(MF)interactions and corrections to them induced by quantum fluctuations[2].Recent theoretical predictions[3,4]and experimental demonstrations[5-10]suggest various possibilities for the creation of novel fundamental and vortical patterns,as summarized in reviews[11-13].In particular,QDs with embedded vorticity were theoretically investigated in detail[14-21].
文摘This item from the News and Views(N&V)category aims to provide a summary of theoretical and experimental results recently published in ref.24,which demonstrates the creation of corner modes in nonlinear optical waveguides of the higher-order topological insulator(HOTI)type.Actually,these are second-order HOTIs,in which the transverse dimension of the topologically protected edge modes is smaller than the bulk dimension(it is 2,in the case of optical waveguide)by 2,implying zero dimension of the protected modes,which are actually realized as corner or defect ones.Work24 reports the prediction and creation of various forms of the corner modes in a HOTI with a fractal transverse structure,represented by the Sierpiński gasket(SG).The self-focusing nonlinearity of the waveguide's material transforms the corner modes into corner solitons,almost all of which are stable.The solitons may be attached to external or internal corners created by the underlying SG.This N&V item offers an overview of these new findings reported in ref.24 and other recent works,and a brief discussion of directions for further work on this topic.
基金Y.L.acknowledges the supports of the National Natural Science Foundation of China(Grant Nos.11874112 and 11905032)the Key Research Projects of General Colleges in Guangdong Province through grant No.2019KZDXM001+1 种基金the Foundation for Distinguished Young Talents in Higher Education of Guangdong through grant No.2018KQNCX279The work of BAM on this topic was supported,in part,by grant No.1286/17 from the Israel Science Foundation.
文摘This brief review summarizes recent theoretical and experimental results which predict and establish the existence of quantum droplets(QDs),i.e.,robust two-and three-dimensional(2D and 3D)self-trapped states in Bose-Einstein condensates(BECs),which are stabilized by effective self-repulsion induced by quantum fluctuations around the mean-field(MF)states[alias the Lee-Huang-Yang(LHY)effect].The basic models are presented,taking special care of the dimension crossover,2D→3D.Recently reported experimental results,which exhibit stable 3D and quasi-2D QDs in binary BECs,with the inter-component attraction slightly exceeding the MF self-repulsion in each component,and in single-component condensates of atoms carrying permanent magnetic moments,are presented in some detail.The summary of theoretical results is focused,chiefly,on 3D and quasi-2D QDs with embedded vorticity,as the possibility to stabilize such states is a remarkable prediction.Stable vortex states are presented both for QDs in free space,and for singular but physically relevant 2D modes pulled to the center by the inverse-square potential,with the quantum collapse suppressed by the LHY effect.
文摘In the course of the past 25 years,several new quantum states of matter have been created in ultracold gases,starting from the celebrated Bose-Einstein condensates(BECs),which were first made in 1995,follow-ing the theoretical prediction published in 1924[1].This achievement was followed by the creation and detailed exploration of degenerate Fermi gases[2].
基金supported by the National Natural Science Foundation of China(NSFC)through Grant Nos.12274077,11874112,12305013,and 11905032the Natural Science Foundation of Guangdong Province through Grant Nos.2021A1515010214 and 2021A1515111015+2 种基金the Key Research Projects of General Colleges in Guangdong Province through Grant No.2019KZDXM001the Research Fund of Guangdong−Hong Kong−Macao Joint Laboratory for Intelligent Micro−Nano Optoelectronic Technology through Grant No.2020B1212030010The work of B.A.M.was supported,in part,by the Israel Science Foundation through Grant No.1695/22.
文摘Creation of stable intrinsically anisotropic self-bound states with embedded vorticity is a challenging issue.Previously,no such states in Bose−Einstein condensates(BECs)or other physical settings were known.Dipolar BEC suggests a unique possibility to predict stable two dimensional anisotropic vortex quantum droplets(2D-AVQDs).We demonstrate that they can be created with the vortex axis oriented perpendicular to the polarization of dipoles.The stability area and characteristics of the 2D-AVQDs in the parameter space are revealed by means of analytical and numerical methods.Further,the rotation of the polarizing magnetic field is considered,and the largest angular velocities,up to which spinning 2D-AVQDs can follow the rotation in clockwise and anti-clockwise directions,are found.Collisions between moving 2D-AVQDs are studied too,demonstrating formation of bound states with a vortex−antivortex−vortex structure.A stability domain for such stationary bound states is identified.Unstable dipolar states,that can be readily implemented by means of phase imprinting,quickly transform into robust 2D-AVQDs,which suggests a straightforward possibility for the creation of these states in the experiment.
