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Nonlinear two-mode squeezing obtained by analysing two-mode exponential quadrature operators in entangled state representation
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作者 刘堂昆 单传家 +1 位作者 刘继兵 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期118-122,共5页
By analysing the properties of two-mode quadratures in an entangled state representation (ESR) we derive from ESR some complicated exponential quadrature operators for nonlinear two-mode squeezing, which directly le... By analysing the properties of two-mode quadratures in an entangled state representation (ESR) we derive from ESR some complicated exponential quadrature operators for nonlinear two-mode squeezing, which directly leads to wave function of the nonlinear squeezed state in ESR. 展开更多
关键词 nonlinear two-mode squeezing two-mode exponential quadrature operators entangled state representation
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Detaching two single-mode squeezing operators from the two-mode squeezing operator
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作者 范洪义 笪诚 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期222-224,共3页
It has been common knowledge that the single-mode squeezing operator and the two-mode squeezing operator are independent of each other. However, in this work we find that after using the technique of integration with... It has been common knowledge that the single-mode squeezing operator and the two-mode squeezing operator are independent of each other. However, in this work we find that after using the technique of integration within Ω-ordering and β-ordering, we can detach two single-mode squeezing operators from the two-mode squeezing operator. In other words, we show that the two-mode squeezing operator can be split into a β-ordered two-mode squeezing operator (with a new squeezing parameter) and two single-mode squeezing operators (with another squeezing parameter). This tells us that the two-mode squeezing mechanism also involves some single-mode squeezing. 展开更多
关键词 Ω-ordering and β-ordering single-mode and two-mode squeezing operators detaching
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Coordinate-Dependent Two-Mode Squeezing Transformations and the Corresponding Squeezed States
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作者 SONG Tong-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期325-329,共5页
We introduce the coordinate-dependent two-mode squeezing transformations and discuss the properties of the corresponding two-mode squeezed states.
关键词 coordinate-dependent two-mode squeezing transformation two-mode squeezed states
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Preparation and control of atomic optimal entropy squeezing states for a moving two-level atom under control of the two-mode squeezing vacuum fields 被引量:2
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作者 周并举 刘一曼 +1 位作者 赵明卓 刘小娟 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期278-284,共7页
From the viewpoint of quantum information, this paper studies preparation and control of atomic optimal entropy squeezing states (AOESS) for a moving two-level atom under control of the two-mode squeezing vacuum fie... From the viewpoint of quantum information, this paper studies preparation and control of atomic optimal entropy squeezing states (AOESS) for a moving two-level atom under control of the two-mode squeezing vacuum fields. Necessary conditions of preparation of the AOESS are analysed, and numerical verification of the AOESS is finished. It shows that the AOESS can be prepared by controlling the time of the atom interaction with the field, cutting the entanglement between the atom and field, and adjusting squeezing factor of the field. An atomic optimal entropy squeezing sudden generation in different components can alternately be realized by controlling the field-mode structure parameter. 展开更多
关键词 atomic optimal entropy squeezing state squeezing factor of the field the field-mode structure parameter
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Coordinate-Dependent One- and Two-Mode Squeezing Transformation and the Corresponding Squeezed States
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作者 REN Gang SONG Tong-Qiang Department of Physics,Ningbo University,Ningbo 315211,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第12期1093-1098,共6页
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
关键词 one-and two-mode squeezed states nonlinear Bogoliubov transformations
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Hydromagnetic Squeezing Nanofluid Flow between Two Vertical Plates in Presence of a Chemical Reaction
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作者 Benjamin Matur Madit Jackson K. Kwanza Phineas Roy Kiogora 《Journal of Applied Mathematics and Physics》 2024年第1期126-146,共21页
In this study, Hydromagnetic Squeezing Nanofluid flow between two vertical plates in presence of a chemical reaction has been investigated. The governing equations were transformed by similarity transformation and the... In this study, Hydromagnetic Squeezing Nanofluid flow between two vertical plates in presence of a chemical reaction has been investigated. The governing equations were transformed by similarity transformation and the resulting ordinary differential equations were solved by collocation method. The velocity, temperature, concentration and magnetic induction profiles were determined with help of various flow parameters. The numerical scheme was simulated with aid of MATLAB. The results showed that increasing the squeeze number only boosts velocity and concentration while lowering temperature. Conversely, increasing the Hartmann number, Reynold’s magnetic number, Eckert number and Thermal Grashof number generally increases temperature but decreases both velocity and concentration. Chemical reaction rate and Soret number solely elevate concentration while Schmidt number only reduces it. The results of this study will be useful in the fields of oil and gas industry, plastic processing industries, filtration, food processing, lubrication system in machinery, Microfluidics devices for drug delivery and other related fields of nanotechnology. 展开更多
关键词 HYDROMAGNETIC squeezing Flow NANOFLUID Variable Magnetic Field Chemical Reaction
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One- and Two-Mode Combination Squeezing Operator for Two Harmonic Oscillators with Coordinate-Momentum Coupling 被引量:1
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作者 FAN Hong-Yi YAN Peng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期428-430,共3页
By virtue of the technique of integration within an ordered product of operators, we derive the normal ordering expansion of a one- and two-mode combination squeezing operator for two harmonic oscillators with coordin... By virtue of the technique of integration within an ordered product of operators, we derive the normal ordering expansion of a one- and two-mode combination squeezing operator for two harmonic oscillators with coordinate- momentum coupling. It turns out that this squeezing operator just diagonalizes the Hamiltonian H=p^21/2m1+m1ω^21x^21/2+p^222m2+m2ω^22x^22/2-λx2p1 so its ground state is a one- and two-mode combination squeezed state. Quantum fluctuation in the ground state is calculated. 展开更多
关键词 one- and two-mode combination squeezing operator coupled oscillator coordinate-momentum coupling
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Entropy squeezing for a two-level atom in two-mode Raman coupled model with intrinsic decoherence 被引量:2
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作者 张剑 邵彬 邹健 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1517-1527,共11页
In this paper, we investigate the entropy squeezing for a two-level atom interacting with two quantized fields through Raman coupling. We obtain the dynamical evolution of the total system under the influence of intri... In this paper, we investigate the entropy squeezing for a two-level atom interacting with two quantized fields through Raman coupling. We obtain the dynamical evolution of the total system under the influence of intrinsic decoherence when the two quantized fields are prepared in a two-mode squeezing vacuum state initially. The effects of the field squeezing factor, the two-level atomic transition frequency, the second field frequency and the intrinsic decoherence on the entropy squeezing are discussed. Without intrinsic decoherence, the increase of field squeezing factor can break the entropy squeezing. The two-level atomic transition frequency changes only the period of oscillation but not the strength of entropy squeezing. The influence of the second field frequency is complicated. With the intrinsic decoherence taken into consideration, the results show that the stronger the intrinsic decoherence is, the more quickly the entropy squeezing will disappear. The increase of the atomic transition frequency can hasten the disappearance of entropy squeezing. 展开更多
关键词 entropy squeezing intrinsic decoherence two-mode Raman coupled model
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Quantum entanglement between the two-mode fields and atomic entropy squeezing in the system of a moving atom interacting with two-mode entangled coherent field 被引量:1
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作者 邹艳 李永平 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2794-2800,共7页
This paper investigates the entropy squeezing of a moving two-level atom interacting with the two-mode entangled coherent field via two-photon transition by using an entropic uncertainty relation and the degree of ent... This paper investigates the entropy squeezing of a moving two-level atom interacting with the two-mode entangled coherent field via two-photon transition by using an entropic uncertainty relation and the degree of entanglement between the two-mode fields by using quantum relative entropy.The results obtained from numerical calculation indicate that the squeezed period,the duration of entropy squeezing and the maximal squeezing can be controlled by appropriately choosing the intensity of the light field,the atomic motion and the field-mode structure.The atomic motion leads to the periodic recovery of the initial maximal degree of entanglement between the two-mode fields.Moreover,there exists a corresponding relation between the time evolution properties of the atomic entropy squeezing and those of the entanglement between the two-mode fields. 展开更多
关键词 entropy squeezing quantum relative entropy atomic motion and field-mode structure two-mode entangled light field
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Optimal entropy squeezing sudden generation and its control for an effective two-level moving atom entanglement with the two-mode coherent fields 被引量:2
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作者 刘小娟 周元俊 方卯发 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2307-2313,共7页
From the viewpoint of quantum information, this paper proposes a concept and a definition of the atomic optimal entropy squeezing sudden generation (AOESSG) for the system of an effective two-level moving atom which... From the viewpoint of quantum information, this paper proposes a concept and a definition of the atomic optimal entropy squeezing sudden generation (AOESSG) for the system of an effective two-level moving atom which entangles with the two-mode coherent fields. It also researches the relationship between the AOESSG and entanglement sudden death of the atom-fields, and discusses the influences of atomic initial state on the AOESSG and obtains the system parameter which controls the AOESSG. 展开更多
关键词 optical entropy squeezing sudden generation effective two-level moving atom entanglement sudden death
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A new two-mode thermo- and squeezing-mixed optical field
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作者 周军 范洪义 宋军 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期27-30,共4页
We propose a new two-mode thermo-and squeezing-mixed optical field, described by the new density operator ρ=1-e^f-|g|^2 e^ga^+b^+e^fa^+a|0〉 f_(bb) 〈0| e^(g*ab), where |0〉_(bb) 〈0| is the b-mode va... We propose a new two-mode thermo-and squeezing-mixed optical field, described by the new density operator ρ=1-e^f-|g|^2 e^ga^+b^+e^fa^+a|0〉 f_(bb) 〈0| e^(g*ab), where |0〉_(bb) 〈0| is the b-mode vacuum, e ^fa^+arepresents the thermo-field, and e^ga^+b^+ indicates squeezing. The photon statistics for ρ is studied by virtue of the method of integration within ordered product(IWOP) of operators. Such a field can be generated when a two-mode squeezed state passes through a one-mode dissipation channel. 展开更多
关键词 thermo-and squeezing-mixing new optical field photon statistics integration within ordered product(IWOP) method
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Supporting structure failure caused by the squeezing tunnel creep and its reinforcement measure 被引量:2
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作者 ZHAO Jin-peng TAN Zhong-sheng +1 位作者 LI Lei WANG Xiu-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1774-1789,共16页
Tunnels deeply buried have high crustal stress and are prone to large deformation disasters when encountering soft rock.The large deformation phenomenon during the construction process of the Maoxian Tunnel on the Che... Tunnels deeply buried have high crustal stress and are prone to large deformation disasters when encountering soft rock.The large deformation phenomenon during the construction process of the Maoxian Tunnel on the Chengdu-Lanzhou Railway is particularly evident.This article focuses on the large deformation problem of the No.1 inclined shaft of the Maoxian Tunnel,and uses on-site monitoring methods to explore the reasons for tunnel structure failure,and analyzes the mechanical behavior of the tunnel structure.By using numerical simulation methods,the effectiveness of the second-layer support in resisting creep loads in tunnels was studied,and the influence of the construction time of the secondlayer support on the mechanical properties of the tunnel was discussed.The results indicate that the first-layer support in the tunnel is a structural failure caused by asymmetric deformation caused by creep,while the second-layer support has a good effect on resisting creep loads.The research results can provide a technical reference for deformation control of squeezing tunnels. 展开更多
关键词 squeezing tunnel Mechanical responses Long-term creep Second-layer support On-site monitoring
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New formulas for normalizing photon-added(-subtracted) two-mode squeezed thermal states 被引量:1
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作者 胡利云 范洪义 张智明 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期312-316,共5页
For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of o... For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators(IWOP) technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented. 展开更多
关键词 two-mode squeezed thermal states NORMALIZATION photon addition and subtraction integration within an ordered product of operators technique
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Security of quantum key distribution using two-mode squeezed states against optimal beam splitter attack 被引量:1
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作者 何广强 朱思维 +1 位作者 郭红斌 曾贵华 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第4期1263-1268,共6页
For the beam splitter attack strategy against quantum key distribution using two-mode squeezed states, the analytical expression of the optimal beam splitter parameter is provided in this paper by applying the Shannon... For the beam splitter attack strategy against quantum key distribution using two-mode squeezed states, the analytical expression of the optimal beam splitter parameter is provided in this paper by applying the Shannon information theory. The theoretical secret information rate after error correction and privacy amplification is given in terms of the squeezed parameter and channel parameters. The results show that the two-mode squeezed state quantum key distribution is secure against an optimal beam splitter attack. 展开更多
关键词 quantum key distribution two-mode squeezed states optimal beam splitter attack
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Quantum Properties of Two-Mode Squeezed Even and Odd Coherent States 被引量:1
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作者 ZHANG Jing WU Wei MENG Shao-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期317-324,共8页
Two new types of quantum states are constructed by applying the operator s(ξ) = exp(ξ* ab - ξa+b+) on the two-mode even and odd coherent states. The mathematical and quantum statistical properties of such st... Two new types of quantum states are constructed by applying the operator s(ξ) = exp(ξ* ab - ξa+b+) on the two-mode even and odd coherent states. The mathematical and quantum statistical properties of such states are investigated. Various nonclassical features of these states, such as squeezing properties, the inter-mode photon bunching, and the violation of Cauchy-Schwarz inequality, are discussed. The Wigner function in these states are studied in detail. 展开更多
关键词 two-mode squeezed even/odd coherent states quantum statistical properties
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Non-Gaussianity dynamics of two-mode squeezed number states subject to different types of noise based on cumulant theory 被引量:1
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作者 Shaohua Xiang Xixiang Zhu Kehui Song 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期181-189,共9页
We provide a measure to characterize the non-Gaussianity of phase-space function of bosonic quantum states based on the cumulant theory. We study the non-Gaussianity dynamics of two-mode squeezed number states by anal... We provide a measure to characterize the non-Gaussianity of phase-space function of bosonic quantum states based on the cumulant theory. We study the non-Gaussianity dynamics of two-mode squeezed number states by analyzing the phase-averaged kurtosis for two different models of decoherence: amplitude damping model and phase damping model.For the amplitude damping model, the non-Gaussianity is very fragile and completely vanishes at a finite time. For the phase damping model, such states exhibit rich non-Gaussian characters. In particular, we obtain a transition time that such states can transform from sub-Gaussianity into super-Gaussianity during the evolution. Finally, we compare our measure with the existing measures of non-Gaussianity under the independent dephasing environment. 展开更多
关键词 NON-GAUSSIANITY CUMULANTS squeezed number states DECOHERENCE
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Quantum Entanglement and Nonlocality Properties of Two-Mode Squeezed Thermal States in a Common-Reservoir Model 被引量:4
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作者 向少华 宋克慧 +1 位作者 文伟 施振刚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期232-238,共7页
We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the ... We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the characteristic function method. We analyze the entanglement dynamics of two-mode squeezed thermal state in this model and show that its entanglement dynamics is strongly determined by the two-mode squeezing parameter and the purity. In particular, we find that two-mode squeezed thermal state with the squeezing parameter r ≤ -(1/2) In √u is extremely fragile and almost does not survive in a common vacuum environment. We investigate the time evolution of nonlocality for two-mode squeezed thermal state in such an environment. It is found that the evolved state loses its nonlocality in the beginning of the evolution, but after a time, the revival of nonlocality can occur. 展开更多
关键词 keytwo-mode squeezed thermal state ENTANGLEMENT Bell's inequality environmental noise
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基于改进SqueezeNet算法的VBE设备电路板元件失效识别研究 被引量:1
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作者 刘隆晨 杨玥坪 +3 位作者 贾志杰 黄宇 唐世雄 谭博洋 《电源学报》 CSCD 北大核心 2024年第3期236-247,共12页
在直流输电系统中,换流阀阀基电子VBE(valve base electronics)设备的稳定运作对维护直流系统安全至关重要。传统的阀基电子设备电路板(VBE板)元件失效检测方法依赖于耗时的人工检查或基于规则的自动化系统,这些方法通常检测效率低下且... 在直流输电系统中,换流阀阀基电子VBE(valve base electronics)设备的稳定运作对维护直流系统安全至关重要。传统的阀基电子设备电路板(VBE板)元件失效检测方法依赖于耗时的人工检查或基于规则的自动化系统,这些方法通常检测效率低下且准确性有限。针对该问题,提出一种基于改进的SqueezeNet深度学习模型的VBE板元件失效区域识别方法。通过引入深度可分离卷积和残差连接,所提改进SqueezeNet模型旨在提高元件失效检测的准确性,同时降低计算资源的需求。在VBE板元件失效数据集上的实验结果表明,所提方法在元件失效检测准确率和运算效率方面均优于传统方法和标准SqueezeNet模型,准确率达到了95.27%,比原模型高出4.45%。不仅提升了VBE板元件失效检测的效率和准确性,而且为电力系统中类似设备的元件失效诊断提供了新的技术参考。 展开更多
关键词 阀基电子设备 squeezeNet模型 元件失效检测 特征提取
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Design of the yielding support used highly deformable elements for a tunnel excavated in squeezing rock
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作者 TIAN Hong-ming TIAN Yun +3 位作者 CHEN Wei-zhong TAN Xian-jun SHU Xiao-yun LIU Xia-lin 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1458-1468,共11页
Yielding support is often used in the squeezing tunnel to prevent damage to the lining induced by large deformation of the surrounding rock.Highly Deformable Elements(HDE)which is often installed along the circumferen... Yielding support is often used in the squeezing tunnel to prevent damage to the lining induced by large deformation of the surrounding rock.Highly Deformable Elements(HDE)which is often installed along the circumferential direction of the shotcrete lining is a common type of yielding support.To determine the yield parameters of HDE,the support characteristic of the lining using HDE and the ground pressure considering strain-softening of soft rock were analyzed by an analytical method.The analytical solution showed that when considering the strain-softening of squeezing ground,the ground pressure has a non-zero minimum value.The minimum value of ground stress can be used to determine the constant yield stress of the HDE,and the corresponding deformation of the minimum ground pressure can be used to determine the deformation capacity of the HDE.Based on the variation in the design constant yield stress and yield displacement of HDE with the in-situ stress and the mechanical parameters of the soft rock,equations were proposed for determining of the yield parameters of the HDE. 展开更多
关键词 Highly deformable elements squeezing tunnel Yielding support Strain-softening behavior
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Ground-state phase diagram,symmetries,excitation spectra and finite-frequency scaling of the two-mode quantum Rabi model
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作者 陈越 刘卯鑫 陈晓松 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期509-521,共13页
We investigate the two-mode quantum Rabi model(QRM)describing the interaction between a two-level atom and a two-mode cavity field.The quantum phase transitions are found when the ratioηof transition frequency of ato... We investigate the two-mode quantum Rabi model(QRM)describing the interaction between a two-level atom and a two-mode cavity field.The quantum phase transitions are found when the ratioηof transition frequency of atom to frequency of cavity field approaches infinity.We apply the Schrieffer–Wolff(SW)transformation to derive the low-energy effective Hamiltonian of the two-mode QRM,thus yielding the critical point and rich phase diagram of quantum phase transitions.The phase diagram consists of four regions:a normal phase,an electric superradiant phase,a magnetic superradiant phase and an electromagnetic superradiant phase.The quantum phase transition between the normal phase and the electric(magnetic)superradiant phase is of second order and associates with the breaking of the discrete Z_(2) symmetry.On the other hand,the phase transition between the electric superradiant phase and the magnetic superradiant phase is of first order and relates to the breaking of the continuous U(1)symmetry.Several important physical quantities,for example the excitation energy and average photon number in the four phases,are derived.We find that the excitation spectra exhibit the Nambu–Goldstone mode.We calculate analytically the higher-order correction and finite-frequency exponents of relevant quantities.To confirm the validity of the low-energy effective Hamiltonians analytically derived by us,the finite-frequency scaling relation of the averaged photon numbers is calculated by numerically diagonalizing the two-mode quantum Rabi Hamiltonian. 展开更多
关键词 two-mode quantum Rabi model superradiant phase transition Nambu–Goldstone mode finite-frequency scaling Schrieffer–Wolff(SW)transformation
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