For studying the interference between two Bose-Einstein condensates we introduce the atomic coherentstate(ACS)in the Schwinger bosonic realization along with the phase operator to directly calculate the interferencepa...For studying the interference between two Bose-Einstein condensates we introduce the atomic coherentstate(ACS)in the Schwinger bosonic realization along with the phase operator to directly calculate the interferencepattern with steady relative phase cos φ.Eigenstates of the density operator of condensates are classified as A CS is alsodemonstrated.The entangled state representation is used in some calculations.展开更多
We propose a scheme to implement ancilla-free 1 to 2 optimal phase covariant quantum cloning with atoms trapped in cavities.In the scheme the W-class state of three atoms,which are individually trapped in three spatia...We propose a scheme to implement ancilla-free 1 to 2 optimal phase covariant quantum cloning with atoms trapped in cavities.In the scheme the W-class state of three atoms,which are individually trapped in three spatially separated cavities,is deterministically generated.Then by the use of this W-class state and detection of the atomic state,an optimal ancilla-free 1 to 2 phase-covariant quantum cloning between two spatially separated trapped atoms can be realized.The scheme is robust for atomic spontaneous decay,cavity decay and photon leakage out of the fiber.In principle,an M+1-atom W-class state can be generated by using such an approach.Thus this scheme also can be generalized to implement 1 to M ancilla-free phase-covariant quantum cloning.展开更多
Zinc(Zn) deficiency in paddy soils is often a problem for rice production.Flooding can decrease metal availability in some noncalcareous soils through different mechanisms associated with soil redox status.Laboratory ...Zinc(Zn) deficiency in paddy soils is often a problem for rice production.Flooding can decrease metal availability in some noncalcareous soils through different mechanisms associated with soil redox status.Laboratory experiments were performed in order to better understand the processes that governed the dynamics of Zn in non-calcareous paddy soils at varying redox potentials(Eh).Airdried non-calcareous soil samples collected from four different paddy field sites in the Philippines were submerged and incubated in a reaction cell with continuous stirring and nitrogen purging for 4 weeks,and then purged with compressed air for another week to reoxidize the system.The Eh of the four soils started at 120 to 300 mV,decreased to —220 to —300 mV after 100 to 250 h of reduction,and was maintained at this low plateau for about 2 weeks before increasing again upon reoxidation.Zinc solubility showed contrasting patterns in the four soils,with two of the soils showing a decrease in soluble Zn as the Eh became low,probably due to zinc sulfide(ZnS) precipitation.In contrast,the other two soils showed that Zn solubility was maintained during the reduced phase which could be due to the competition with iron(Fe) for precipitation with sulfide.Differences in the relative amounts of S,Fe,and manganese(Mn) oxides in the four soils apparently influenced the pattern of Zn solubility after flooding.展开更多
基金supported by the President Foundation of the Chinese Academy of Sciencesthe Specialized Research Fund for the Doctorial Progress of Higher Education(SRFDP)under Grant No.20040358019
文摘For studying the interference between two Bose-Einstein condensates we introduce the atomic coherentstate(ACS)in the Schwinger bosonic realization along with the phase operator to directly calculate the interferencepattern with steady relative phase cos φ.Eigenstates of the density operator of condensates are classified as A CS is alsodemonstrated.The entangled state representation is used in some calculations.
基金supported by the National Natural Science Foundation of China (Grant No.11074002)the Personal Development Foundation of Anhui Province (Grant No.2008Z018)
文摘We propose a scheme to implement ancilla-free 1 to 2 optimal phase covariant quantum cloning with atoms trapped in cavities.In the scheme the W-class state of three atoms,which are individually trapped in three spatially separated cavities,is deterministically generated.Then by the use of this W-class state and detection of the atomic state,an optimal ancilla-free 1 to 2 phase-covariant quantum cloning between two spatially separated trapped atoms can be realized.The scheme is robust for atomic spontaneous decay,cavity decay and photon leakage out of the fiber.In principle,an M+1-atom W-class state can be generated by using such an approach.Thus this scheme also can be generalized to implement 1 to M ancilla-free phase-covariant quantum cloning.
基金supported by the Global Rice Science Partnership(GRiSP) Staff Development Fundthe Swiss Agency for Development and Cooperation(SDC) awarded to Dr.S.M.Impa,International Rice Research Institute,Philippines,through its Research Fellow Partnership Programme
文摘Zinc(Zn) deficiency in paddy soils is often a problem for rice production.Flooding can decrease metal availability in some noncalcareous soils through different mechanisms associated with soil redox status.Laboratory experiments were performed in order to better understand the processes that governed the dynamics of Zn in non-calcareous paddy soils at varying redox potentials(Eh).Airdried non-calcareous soil samples collected from four different paddy field sites in the Philippines were submerged and incubated in a reaction cell with continuous stirring and nitrogen purging for 4 weeks,and then purged with compressed air for another week to reoxidize the system.The Eh of the four soils started at 120 to 300 mV,decreased to —220 to —300 mV after 100 to 250 h of reduction,and was maintained at this low plateau for about 2 weeks before increasing again upon reoxidation.Zinc solubility showed contrasting patterns in the four soils,with two of the soils showing a decrease in soluble Zn as the Eh became low,probably due to zinc sulfide(ZnS) precipitation.In contrast,the other two soils showed that Zn solubility was maintained during the reduced phase which could be due to the competition with iron(Fe) for precipitation with sulfide.Differences in the relative amounts of S,Fe,and manganese(Mn) oxides in the four soils apparently influenced the pattern of Zn solubility after flooding.