The Efimov(Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64)Zn(64 Ni)+ 70(64)Zn(64 Ni) reactions at the beam energy of E/A...The Efimov(Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64)Zn(64 Ni)+ 70(64)Zn(64 Ni) reactions at the beam energy of E/A = 35 MeV/nucleon. In heavy ion collisions, a-particles interact with each other and can form complex systems such as 8 Be and 12 C. For the 3 a-particle systems,multi-resonance processes give rise to excited levels of 12 C. The interaction between any two of the 3 a-particles provides events with one, two or three 8 Be. Their interfering levels are clearly seen in the minimum relative energy distributions. Events with the three a-particle relative energies consistent with the ground state of 8 Be are observed with the decrease of the instrumental error for the reconstructed 7.458 MeV excitation level in 12 C, which was suggested as the Efimov(Thomas) state.展开更多
The Efimov effect is defined as a quantum state with discrete scaling symmetry and a universal scaling factor. It has attracted considerable interests from nuclear to atomic physics communities. In a Dirac semi-metal,...The Efimov effect is defined as a quantum state with discrete scaling symmetry and a universal scaling factor. It has attracted considerable interests from nuclear to atomic physics communities. In a Dirac semi-metal, when an electron interacts with a static impurity through a Coulombic interaction, the same kinetic scaling and the interaction energy results in the Efimov effect. However, even when the Fermi energy lies exactly at the Dirac point, the vacuum polarization of the electron-hole pair fluctuation can still screen the Coulombic interaction, which leads to deviations from the scaling symmetry and eventually breaks down of the Efimov effect. This energy distortion of the Efimov states due to vacuum polarization is a relativistic electron analogy of the Lamb shift for the hydrogen atom. Motivated by the recent experimental observations in two- and three-dimensional Dirac semi-metals, we herein investigate this many-body correction to the Efimov effect and the conditions that allow some of the Efimov-like quasi-bound states to be observed in these condensed matter experiments.展开更多
We propose a scheme to produce a uniform magnetic field with a system comprising a pair of coils and an atom chip. After optimizing the parameters of the chip wires, we improve the homogeneity of the magnetic field by...We propose a scheme to produce a uniform magnetic field with a system comprising a pair of coils and an atom chip. After optimizing the parameters of the chip wires, we improve the homogeneity of the magnetic field by two orders of magnitude. We exhibit that this method can be applied in the investigation of Efimov physics in 87Rb-40K mixture.展开更多
In this work,the existence of Borromean states is discussed for bosonic and fermionic cases in both therelativistic and non-relativistic limits from the 3-momentum shell renormalization.With the linear bosonic model,w...In this work,the existence of Borromean states is discussed for bosonic and fermionic cases in both therelativistic and non-relativistic limits from the 3-momentum shell renormalization.With the linear bosonic model,we check the existence of Efimov-like states in the bosonic system.In both limits a geometric series of singularities is found in the 3-boson interaction vertex,while the energy ratio is reduced by around 70%in the relativistic limit because of the anti-particle contribution.Motivated by the quark-diquark model in heavy baryon studies,we have carefully examined the p-wave quark-diquark interaction and found an isolated Borromean pole at finite energy scale.This may indicate a special baryonic state of light quarks in high energy quark matter.In other cases,trivialresults are obtained as expected.In the relativistic limit,for both bosonic and fermionic cases,potential Borromean states are independent of the mass,which means the results would also be valid even in the zero-mass limit.展开更多
Engineering lattice models with tailored inter-site tunnelings and onsite energies could synthesize essentially arbitrary Riemannian surfaces with highly tunable local curvatures.Here,we point out that discrete synthe...Engineering lattice models with tailored inter-site tunnelings and onsite energies could synthesize essentially arbitrary Riemannian surfaces with highly tunable local curvatures.Here,we point out that discrete synthetic Poincaréhalf-planes and Poincarédisks,which are created by lattices in flat planes,support infinitely degenerate eigenstates for any nonzero eigenenergies.Such Efimov-like states exhibit a discrete scaling symmetry and imply an unprecedented apparatus for studying quantum anomaly using hyperbolic surfaces.Furthermore,all eigenstates are exponentially localized in the hyperbolic coordinates,signifying the first example of quantum funneling effects in Hermitian systems.As such,any initial wave packet travels towards the edge of the Poincaréhalf-plane or its equivalent on the Poincarédisk,delivering an efficient scheme to harvest light and atoms in two dimensions.Our findings unfold the intriguing properties of hyperbolic spaces and suggest that Efimov states may be regarded as a projection from a curved space with an extra dimension.展开更多
基金Supported by the National Natural Science Foundation of China(1176014,11605097,11421505,11865010)the US Department of Energy(DE-FG02-93ER40773,NNSA DE-NA0003841(CENTAUR))+6 种基金the Robert A.Welch Foundation(A-1266)supported by the Chinese Academy of Sciences(CAS)President’s International Fellowship Initiative(2015VWA070)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB16 and XDPB09)Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT-18-B21)Doctoral Scientific Research Foundation of Inner Mongolia University for Nationalities(BS365 and BS400)The Fundamental Research Funds for the Central Universities(GK201903022)Natural Science Foundation of Inner Mongolia(2018MS01009)
文摘The Efimov(Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64)Zn(64 Ni)+ 70(64)Zn(64 Ni) reactions at the beam energy of E/A = 35 MeV/nucleon. In heavy ion collisions, a-particles interact with each other and can form complex systems such as 8 Be and 12 C. For the 3 a-particle systems,multi-resonance processes give rise to excited levels of 12 C. The interaction between any two of the 3 a-particles provides events with one, two or three 8 Be. Their interfering levels are clearly seen in the minimum relative energy distributions. Events with the three a-particle relative energies consistent with the ground state of 8 Be are observed with the decrease of the instrumental error for the reconstructed 7.458 MeV excitation level in 12 C, which was suggested as the Efimov(Thomas) state.
文摘The Efimov effect is defined as a quantum state with discrete scaling symmetry and a universal scaling factor. It has attracted considerable interests from nuclear to atomic physics communities. In a Dirac semi-metal, when an electron interacts with a static impurity through a Coulombic interaction, the same kinetic scaling and the interaction energy results in the Efimov effect. However, even when the Fermi energy lies exactly at the Dirac point, the vacuum polarization of the electron-hole pair fluctuation can still screen the Coulombic interaction, which leads to deviations from the scaling symmetry and eventually breaks down of the Efimov effect. This energy distortion of the Efimov states due to vacuum polarization is a relativistic electron analogy of the Lamb shift for the hydrogen atom. Motivated by the recent experimental observations in two- and three-dimensional Dirac semi-metals, we herein investigate this many-body correction to the Efimov effect and the conditions that allow some of the Efimov-like quasi-bound states to be observed in these condensed matter experiments.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11674338,11791240178,and 11547024)Innovation Training Programs for Undergraduates,Chinese Academy of Sciences(Grant No.KCJH-80140-2016-018)
文摘We propose a scheme to produce a uniform magnetic field with a system comprising a pair of coils and an atom chip. After optimizing the parameters of the chip wires, we improve the homogeneity of the magnetic field by two orders of magnitude. We exhibit that this method can be applied in the investigation of Efimov physics in 87Rb-40K mixture.
基金Supported by the National Natural Science Foundation of China (11875002, 11804376)Postdoctoral Innovative Talent Support Program of China (BX20190180)supported by the Zhuobai Program of Beihang University。
文摘In this work,the existence of Borromean states is discussed for bosonic and fermionic cases in both therelativistic and non-relativistic limits from the 3-momentum shell renormalization.With the linear bosonic model,we check the existence of Efimov-like states in the bosonic system.In both limits a geometric series of singularities is found in the 3-boson interaction vertex,while the energy ratio is reduced by around 70%in the relativistic limit because of the anti-particle contribution.Motivated by the quark-diquark model in heavy baryon studies,we have carefully examined the p-wave quark-diquark interaction and found an isolated Borromean pole at finite energy scale.This may indicate a special baryonic state of light quarks in high energy quark matter.In other cases,trivialresults are obtained as expected.In the relativistic limit,for both bosonic and fermionic cases,potential Borromean states are independent of the mass,which means the results would also be valid even in the zero-mass limit.
基金National Natural Science Foundation of China(10535010,10735010 ,10775068)Major State Basic Research and Development Programof China(973 Program)(2007CB815004)+1 种基金Knowledge Innvation Project of Chinese Academy of Sciences(KJCX2-SW-No2)Doctoral Fund of Ministry of Education of China(RFDP 20070284016)~~
基金supported by the National Natural Science Foundation of China(11804268)the National Key R&D Program of China(2018YFA0307601)。
文摘Engineering lattice models with tailored inter-site tunnelings and onsite energies could synthesize essentially arbitrary Riemannian surfaces with highly tunable local curvatures.Here,we point out that discrete synthetic Poincaréhalf-planes and Poincarédisks,which are created by lattices in flat planes,support infinitely degenerate eigenstates for any nonzero eigenenergies.Such Efimov-like states exhibit a discrete scaling symmetry and imply an unprecedented apparatus for studying quantum anomaly using hyperbolic surfaces.Furthermore,all eigenstates are exponentially localized in the hyperbolic coordinates,signifying the first example of quantum funneling effects in Hermitian systems.As such,any initial wave packet travels towards the edge of the Poincaréhalf-plane or its equivalent on the Poincarédisk,delivering an efficient scheme to harvest light and atoms in two dimensions.Our findings unfold the intriguing properties of hyperbolic spaces and suggest that Efimov states may be regarded as a projection from a curved space with an extra dimension.