We have proposed a quantum system with equally-distant partially-entangled alphabet states which hasthe minimal mutual overlap and the highly distinguishability, these quantum states are used as the "signal state...We have proposed a quantum system with equally-distant partially-entangled alphabet states which hasthe minimal mutual overlap and the highly distinguishability, these quantum states are used as the "signal states" ofthe quantum communication. We have also constructed the positive operator-valued measure for these "signal states"and discussed their entanglement properties and measurement of cntanglement. We calculate the accessible informationfor these alphabet states and show that the accessible information is closely related to the entanglement of the "signalstates": the higher the entanglement of the "signal states", the better the accessible information of the quantum system.and the accessible information reaches its maximal value when the alphabet states have their maximal entanglemcnt.展开更多
We reveal that the common eigenvector of two particles' center-of-mass coordinate and mass-weightedrelative momentum is an entangled state. Its Schmidt decomposition exhibits that the entanglement involves squeezi...We reveal that the common eigenvector of two particles' center-of-mass coordinate and mass-weightedrelative momentum is an entangled state. Its Schmidt decomposition exhibits that the entanglement involves squeezingwhich depends on the ratio of two particles' masses. The corresponding entangling operators are derived.展开更多
A method is presented for generating highly squeezed states of a cavity field via the atom-cavity field interaction of the Raman type. In the scheme a sequence of three-level A-type atoms interacts with a cavity field...A method is presented for generating highly squeezed states of a cavity field via the atom-cavity field interaction of the Raman type. In the scheme a sequence of three-level A-type atoms interacts with a cavity field, displaced by a classical source, in a Rarman manner. Then the atomic states are measured. By this way the cavity field may collapse onto a superposition of several coherent states, which exhibits strong squeezing. The scheme can also be used to prepare superpositions of many two-mode coherent states for two cavity fields. The coherent states in each mode are on a straight line. This is the first way for preparing multi-component entangled coherent states of this type in cavity QED.展开更多
文摘We have proposed a quantum system with equally-distant partially-entangled alphabet states which hasthe minimal mutual overlap and the highly distinguishability, these quantum states are used as the "signal states" ofthe quantum communication. We have also constructed the positive operator-valued measure for these "signal states"and discussed their entanglement properties and measurement of cntanglement. We calculate the accessible informationfor these alphabet states and show that the accessible information is closely related to the entanglement of the "signalstates": the higher the entanglement of the "signal states", the better the accessible information of the quantum system.and the accessible information reaches its maximal value when the alphabet states have their maximal entanglemcnt.
文摘We reveal that the common eigenvector of two particles' center-of-mass coordinate and mass-weightedrelative momentum is an entangled state. Its Schmidt decomposition exhibits that the entanglement involves squeezingwhich depends on the ratio of two particles' masses. The corresponding entangling operators are derived.
文摘A method is presented for generating highly squeezed states of a cavity field via the atom-cavity field interaction of the Raman type. In the scheme a sequence of three-level A-type atoms interacts with a cavity field, displaced by a classical source, in a Rarman manner. Then the atomic states are measured. By this way the cavity field may collapse onto a superposition of several coherent states, which exhibits strong squeezing. The scheme can also be used to prepare superpositions of many two-mode coherent states for two cavity fields. The coherent states in each mode are on a straight line. This is the first way for preparing multi-component entangled coherent states of this type in cavity QED.
