By converting the triangular functions in the integration kernel of the fractional Fourier transformation to the hyperbolic function,i.e.,tan α → tanh α,sin α →〉 sinh α,we find the quantum mechanical fractional...By converting the triangular functions in the integration kernel of the fractional Fourier transformation to the hyperbolic function,i.e.,tan α → tanh α,sin α →〉 sinh α,we find the quantum mechanical fractional squeezing transformation（FrST） which satisfies additivity.By virtue of the integration technique within the ordered product of operators（IWOP） we derive the unitary operator responsible for the FrST,which is composite and is made of e^iπa＋a/2 and exp[iα/2（a^2 ＋a^＋2）.The FrST may be implemented in combinations of quadratic nonlinear crystals with different phase mismatches.展开更多
By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)operator.The way we successfu...By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)operator.The way we successfully combine them to realize the integration transform kernel of WFr ST is making full use of the completeness relation of Dirac’s ket–bra representation.The WFr ST can play role in analyzing and recognizing quantum states,for instance,we apply this new transform to identify the vacuum state,the single-particle state,and their superposition state.展开更多
Based on the fact that the quantum mechanical version of Hankel transform kernel（the Bessel function） is just the transform between ｜q, r〉 and（s, r′｜, two induced entangled state representations are given, and ...Based on the fact that the quantum mechanical version of Hankel transform kernel（the Bessel function） is just the transform between ｜q, r〉 and（s, r′｜, two induced entangled state representations are given, and working with them we derive fractional squeezing-Hankel transform（FrSHT） caused by the operator e（-iα）（a1-a-2-＋a-1a-2）e-（-iπa2-a2）, which is an entangled fractional squeezing transform operator. The additive rule of the FrSHT can be explicitly proved.展开更多
By establishing the relation between the optical scaled fractional Fourier transform （FFT） and quantum mechanical squeezing-rotating operator transform, we employ the bipartite entangled state representation of two-...By establishing the relation between the optical scaled fractional Fourier transform （FFT） and quantum mechanical squeezing-rotating operator transform, we employ the bipartite entangled state representation of two-mode squeezing operator to extend the scaled FFT to more general cases, such as scaled complex FFT and entangled scaled FFT. The additiyity and eigenmodes are presented in quantum version. The relation between the scaled FFT and squeezing-rotating Wigner operator is studied.展开更多
The four-particle EPR entangled state 【 p, X2,X3,X4 】 is constructed. Thecorresponding quantum mechanical operator with respect to the classical transformation p → e~(λ1)p, X2 → e~(λ2)X2, X3 → e~(λ3) X3, and ...The four-particle EPR entangled state 【 p, X2,X3,X4 】 is constructed. Thecorresponding quantum mechanical operator with respect to the classical transformation p → e~(λ1)p, X2 → e~(λ2)X2, X3 → e~(λ3) X3, and X4 → ee~(λ4) X4 in the state 【 p, X2, X3, X4 】 isinvestigated, and the four-mode realization of the S U(1, 1) Lie algebra as well as thecorresponding squeezing operators are presented.展开更多
Using squeezing transform in the context of quantum optics and based on the Fourier series expansion we rigorously derive a new Poisson sum formula. Application of this new formula to the representation transformation...Using squeezing transform in the context of quantum optics and based on the Fourier series expansion we rigorously derive a new Poisson sum formula. Application of this new formula to the representation transformation of kq-wave function for describing electrons in periodic lattice is demonstrated. In so doing, the transition matrix element of harmonic oscillator in kq representation is derived.展开更多
We introduce the coordinate-dependent N-mode squeezing transformation and show that it cain be constructed by the combination of two unitary transformations, a coordinate-dependent displacement followed by the standar...We introduce the coordinate-dependent N-mode squeezing transformation and show that it cain be constructed by the combination of two unitary transformations, a coordinate-dependent displacement followed by the standard squeezed transformation. The properties of the corresponding N-mode squeezed states are also discussed.展开更多
We introduce the coordinate-dependent one-and two-mode squeezing transformations and discuss theproperties of the corresponding one-and two-mode squeezed states.We show that the coordinate-dependent one-and two-mode s...We introduce the coordinate-dependent one-and two-mode squeezing transformations and discuss theproperties of the corresponding one-and two-mode squeezed states.We show that the coordinate-dependent one-and two-mode squeezing transformations can be constructed by the combination of two transformations,a coordinate-dependentdisplacement followed by the standard squeezed transformation.Such a decomposition turns a nonlinear problem intoa linear one because all the calculations involving the nonlinear one-and two-mode squeezed transformation have beenshown to be able to reduce to those only concerning the standard one-and two-mode squeezed states.展开更多
We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed ｜p, X2, X3〉→μ^-3/2｜p/μ, X2/μ, X3/μ） and the optical implement to...We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed ｜p, X2, X3〉→μ^-3/2｜p/μ, X2/μ, X3/μ） and the optical implement to realize such a squeezed state. We also reveal that c-number .asymmetric shrink transform in the three-mode entangled state, i.e. ｜p, X2,X3）→μ^-1/2｜p/μ, X2,X3）, maps onto a kind of one-sided three-mode squeezing operator {iλ （∑i^3=1 Pi） （∑i^3=1 Qi） -λ/2}. Using the technique of integration within an ordered product （IWOP） of operators, we derive their normally ordered forms and construct the corresponding squeezed states.展开更多
By means of the invariance of Weyl ordering under similar transformations we derive the explicit form of the generalized multimode squeezed states. Moreover, the completeness relation and the squeezing properties of t...By means of the invariance of Weyl ordering under similar transformations we derive the explicit form of the generalized multimode squeezed states. Moreover, the completeness relation and the squeezing properties of the generalized multimode squeezed states are discussed.展开更多
We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±,...We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±, Jz） from the point of view of squeezing we find that （J±,Jz） can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation （the eigenvectors of J＋ or J-） of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU（2） transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU（2） and new squeezing operators.展开更多
【目的】针对静偏心挤压油膜阻尼器(Squeeze Film Damper,SFD)产生的周期时变动力特性识别难题,提出一种高精度的参数识别方法。【方法】首先,将经验小波变换(Empirical Wavelet Transform,EWT)应用于静偏心SFD的动力特性识别中;然后,利...【目的】针对静偏心挤压油膜阻尼器(Squeeze Film Damper,SFD)产生的周期时变动力特性识别难题,提出一种高精度的参数识别方法。【方法】首先,将经验小波变换(Empirical Wavelet Transform,EWT)应用于静偏心SFD的动力特性识别中;然后,利用EWT自适应划分信号频谱,提取具有紧支撑傅里叶频谱的有效调幅-调频分量,并结合最小二乘法求解系统的时变刚度与阻尼参数。【结果】仿真分析表明,所提方法能够准确识别单自由度质量-弹簧系统的时变动力学参数。通过对SFD双向激励试验数据的处理,成功获取了阻尼器随周期变化的刚度与阻尼特性。研究证明,所提EWT方法可以有效支撑SFD的优化设计与动力学评价。展开更多
We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on n...We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on numberstate can be easily derived.展开更多
With the help of su(2) algebra technique, a new equivalent form of the fractional Fourier transformation is given. Two examples are illustrated for their physical application in quantum optics.
In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuti...In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuting operators. Addressing this issue, a nonstandard unitary transformation technique is highlighted here with new perspective. In a spirit of “quantum” series expansions, the transition probabilities between initial and final states, such as displaced, squeezed and other nonlinearly transformed coherent states are obtained both numerically and analytically. This paper concludes that, although this technique is novel, its implementations for more extended systems are needed.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11304126)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20130532)+2 种基金the Natural Science Fund for Colleges and Universities in Jiangsu Province,China(Grant No.13KJB140003)the Postdoctoral Science Foundation of China(Grant No.2013M541608)the Postdoctoral Science Foundation of Jiangsu Province,China(Grant No.1202012B)
文摘By converting the triangular functions in the integration kernel of the fractional Fourier transformation to the hyperbolic function,i.e.,tan α → tanh α,sin α →〉 sinh α,we find the quantum mechanical fractional squeezing transformation（FrST） which satisfies additivity.By virtue of the integration technique within the ordered product of operators（IWOP） we derive the unitary operator responsible for the FrST,which is composite and is made of e^iπa＋a/2 and exp[iα/2（a^2 ＋a^＋2）.The FrST may be implemented in combinations of quadratic nonlinear crystals with different phase mismatches.
基金supported by the National Natural Science Foundation of China(Grant No.11304126)the College Students’Innovation Training Program(Grant No.202110299696X)。
文摘By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)operator.The way we successfully combine them to realize the integration transform kernel of WFr ST is making full use of the completeness relation of Dirac’s ket–bra representation.The WFr ST can play role in analyzing and recognizing quantum states,for instance,we apply this new transform to identify the vacuum state,the single-particle state,and their superposition state.
基金Project supported by the National Natural Science Foundation of China(Grant No.11304126)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20130532)
文摘Based on the fact that the quantum mechanical version of Hankel transform kernel（the Bessel function） is just the transform between ｜q, r〉 and（s, r′｜, two induced entangled state representations are given, and working with them we derive fractional squeezing-Hankel transform（FrSHT） caused by the operator e（-iα）（a1-a-2-＋a-1a-2）e-（-iπa2-a2）, which is an entangled fractional squeezing transform operator. The additive rule of the FrSHT can be explicitly proved.
基金National Natural Science Foundation of China under Grant Nos.10775097,10874174,and 10647133the Natural Science Foundation of Jiangxi Province under Grant Nos.2007GQS1906 and 2007GZS1871the Research Foundation of the Education Department of Jiangxi Province under Grant No.[2007]22
文摘By establishing the relation between the optical scaled fractional Fourier transform （FFT） and quantum mechanical squeezing-rotating operator transform, we employ the bipartite entangled state representation of two-mode squeezing operator to extend the scaled FFT to more general cases, such as scaled complex FFT and entangled scaled FFT. The additiyity and eigenmodes are presented in quantum version. The relation between the scaled FFT and squeezing-rotating Wigner operator is studied.
基金Open Foundation of Laboratory of High-intensity Optics，中国科学院资助项目
文摘The four-particle EPR entangled state 【 p, X2,X3,X4 】 is constructed. Thecorresponding quantum mechanical operator with respect to the classical transformation p → e~(λ1)p, X2 → e~(λ2)X2, X3 → e~(λ3) X3, and X4 → ee~(λ4) X4 in the state 【 p, X2, X3, X4 】 isinvestigated, and the four-mode realization of the S U(1, 1) Lie algebra as well as thecorresponding squeezing operators are presented.
基金Supported by the President Foundation of Chinese Academy of Sciencethe Specialized Research Fund for the Doctorial Progress of Higher Education in China under Grant No. 20070358009
文摘Using squeezing transform in the context of quantum optics and based on the Fourier series expansion we rigorously derive a new Poisson sum formula. Application of this new formula to the representation transformation of kq-wave function for describing electrons in periodic lattice is demonstrated. In so doing, the transition matrix element of harmonic oscillator in kq representation is derived.
文摘We introduce the coordinate-dependent N-mode squeezing transformation and show that it cain be constructed by the combination of two unitary transformations, a coordinate-dependent displacement followed by the standard squeezed transformation. The properties of the corresponding N-mode squeezed states are also discussed.
文摘We introduce the coordinate-dependent one-and two-mode squeezing transformations and discuss theproperties of the corresponding one-and two-mode squeezed states.We show that the coordinate-dependent one-and two-mode squeezing transformations can be constructed by the combination of two transformations,a coordinate-dependentdisplacement followed by the standard squeezed transformation.Such a decomposition turns a nonlinear problem intoa linear one because all the calculations involving the nonlinear one-and two-mode squeezed transformation have beenshown to be able to reduce to those only concerning the standard one-and two-mode squeezed states.
基金Open Foundation of Laboratory of High- Intensity Optics
文摘We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed ｜p, X2, X3〉→μ^-3/2｜p/μ, X2/μ, X3/μ） and the optical implement to realize such a squeezed state. We also reveal that c-number .asymmetric shrink transform in the three-mode entangled state, i.e. ｜p, X2,X3）→μ^-1/2｜p/μ, X2,X3）, maps onto a kind of one-sided three-mode squeezing operator {iλ （∑i^3=1 Pi） （∑i^3=1 Qi） -λ/2}. Using the technique of integration within an ordered product （IWOP） of operators, we derive their normally ordered forms and construct the corresponding squeezed states.
文摘By means of the invariance of Weyl ordering under similar transformations we derive the explicit form of the generalized multimode squeezed states. Moreover, the completeness relation and the squeezing properties of the generalized multimode squeezed states are discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.11175113 and 11275123)the Key Project of Natural Science Fund of Anhui Province,China(Grant No.KJ2013A261)
文摘We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±, Jz） from the point of view of squeezing we find that （J±,Jz） can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation （the eigenvectors of J＋ or J-） of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU（2） transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU（2） and new squeezing operators.
文摘【目的】针对静偏心挤压油膜阻尼器(Squeeze Film Damper,SFD)产生的周期时变动力特性识别难题,提出一种高精度的参数识别方法。【方法】首先,将经验小波变换(Empirical Wavelet Transform,EWT)应用于静偏心SFD的动力特性识别中;然后,利用EWT自适应划分信号频谱,提取具有紧支撑傅里叶频谱的有效调幅-调频分量,并结合最小二乘法求解系统的时变刚度与阻尼参数。【结果】仿真分析表明,所提方法能够准确识别单自由度质量-弹簧系统的时变动力学参数。通过对SFD双向激励试验数据的处理,成功获取了阻尼器随周期变化的刚度与阻尼特性。研究证明,所提EWT方法可以有效支撑SFD的优化设计与动力学评价。
文摘We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on numberstate can be easily derived.
文摘With the help of su(2) algebra technique, a new equivalent form of the fractional Fourier transformation is given. Two examples are illustrated for their physical application in quantum optics.
文摘In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuting operators. Addressing this issue, a nonstandard unitary transformation technique is highlighted here with new perspective. In a spirit of “quantum” series expansions, the transition probabilities between initial and final states, such as displaced, squeezed and other nonlinearly transformed coherent states are obtained both numerically and analytically. This paper concludes that, although this technique is novel, its implementations for more extended systems are needed.
