Letϕbe a smooth radial weight that decays faster than the class Gaussian ones.We obtain certain estimates for the reproducing kernels and the Lp-estimates for solutions of theδ-equation on the weighted Fock spaces F_...Letϕbe a smooth radial weight that decays faster than the class Gaussian ones.We obtain certain estimates for the reproducing kernels and the Lp-estimates for solutions of theδ-equation on the weighted Fock spaces F_(ϕ)^(p)(1≤p≤∞),which extends the classical Hörmander Theorem.Furthermore,for a suitable f,we completely characterize the boundedness and compactness of the Hankel operator H_(f):F_(ϕ)^(p)→L^(q)(C,e^(qϕ(·))dm)for all possible 1≤p,q<∞and also characterize the Schatten-p class Hankel operator Hf from F_(ϕ)^(2)to L^(2)(C,E^(-2ϕ)dm) for all 0<p<∞. As an application, we give a complete characterization of the simultaneously bounded, compact and Schatten-p classes Hankel operators H_(f) and h_(f)^(-) on F_(ϕ)^(2).展开更多
In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equ...In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equivalent characterizations for invertible Toeplitz operators Tψ,induced by positive bounded symbols φ on F^(2)_(φ).展开更多
In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson ...In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson condition,bounded Toeplitz operators,compact Toeplitz operators,and Toeplitz operators in the Schatten-p class are all considered.展开更多
In this paper,the authors study the integral operator■induced by a kernel functionφ(z,·)∈F_α~∞between Fock spaces.For 1≤p≤∞,they prove that S_φ:F_α^(1)→F_α^(p)is bounded if and only if■where k_(a)is ...In this paper,the authors study the integral operator■induced by a kernel functionφ(z,·)∈F_α~∞between Fock spaces.For 1≤p≤∞,they prove that S_φ:F_α^(1)→F_α^(p)is bounded if and only if■where k_(a)is the normalized reproducing kernel of F_α^(2);and,S_φ:F_α^(1)→F_α^(p)is compact if and only if■When 1<q≤∞,it is also proved that the condition(?)is not sufficient for boundedness of S_φ:F_α^(q)→F_α^(p).In the particular case■with ■∈F^(2)_α,for 1≤q<p<∞,they show that S_φ:F^(p)_α→F^(q)_αis bounded if and only if■;for 1<p≤q<∞,they give sufficient conditions for the boundedness or compactness of the operator S^(q)_φ:F^(p)_α→F_α.展开更多
In this paper,we characterize the boundedness and compactness of the block dual Toeplitz operators acting on the orthogonal complement of the Fock spaces,and the compactness of the finite sum of two dual Toeplitz oper...In this paper,we characterize the boundedness and compactness of the block dual Toeplitz operators acting on the orthogonal complement of the Fock spaces,and the compactness of the finite sum of two dual Toeplitz operators products.The commutator and semi-commutator induced by the block dual Toeplitz operators are considered.展开更多
The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(...The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given.展开更多
In this paper, we discuss the Schatten-p class （0 〈 p≤∞ ） of Toeplitz operators on generalized Foek space with the symbol in positive Borel measure. It makes a great difference from other papers by using the esti...In this paper, we discuss the Schatten-p class （0 〈 p≤∞ ） of Toeplitz operators on generalized Foek space with the symbol in positive Borel measure. It makes a great difference from other papers by using the estimates of the kernel and the weight together instead of separately estimating each other. We also get the equivalent conditions when a Toeplitz operator is in the Schatten-p class.展开更多
In this paper,cohyponormal weighted composition operators on the Fock space over C^(N)are characterized completely.We also consider a class of weighted composition operators on the Fock space over C^(N)which are both ...In this paper,cohyponormal weighted composition operators on the Fock space over C^(N)are characterized completely.We also consider a class of weighted composition operators on the Fock space over C^(N)which are both posinormal and coposinormal.As an application,we obtain the characterization of hyponormal,cohyponormal,posinormal and coposinormal composition operators on the Fock space over C^(N).展开更多
This paper studies a class of weighted composition operators and their spectrum on the Fock space. As an application, bounded self-adjoint, a class of complex symmetric weighted composition operators on the Fock space...This paper studies a class of weighted composition operators and their spectrum on the Fock space. As an application, bounded self-adjoint, a class of complex symmetric weighted composition operators on the Fock space are characterized.展开更多
Based on a new characterization of bounded and compact weighted compositionoperators on the Fock space obtained by Le T （Le T. Normal and isometricweighted composition operators on the Fock space. Bull. London. Math....Based on a new characterization of bounded and compact weighted compositionoperators on the Fock space obtained by Le T （Le T. Normal and isometricweighted composition operators on the Fock space. Bull. London. Math. Soc., 2014,46： 847-856）, this paper shows that a bounded weighted composition operator onthe Fock space is a Fredholm operator if and only if it is an invertible operator, andif and only if it is a nonzero constant multiple of a unitary operator. The result isvery different from the corresponding results on the Hardy space and the Bergmanspace.展开更多
In this paper,we study bounded(linear and anti-linear)weighted composition operators on the symmetric Fock space over a separable Hilbert space.The unitary and self-adjoint weighted composition operators are character...In this paper,we study bounded(linear and anti-linear)weighted composition operators on the symmetric Fock space over a separable Hilbert space.The unitary and self-adjoint weighted composition operators are characterized completely.A class of normal weighted composition operators is considered.展开更多
We study the effect of electron-phonon （e-ph） interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The...We study the effect of electron-phonon （e-ph） interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The model is constructed using Green＇s function and multi-channel techniques, taking into account the local and nonlocal e-ph interactions. Then, we examine the model for the gapless （simple chain） and gapped （PA-like nanowire） systems. The results show that the tunneling conductance is improved by the e-ph interaction in both local and nonlocal regimes, while for the resonance conductance, the coherent part mainly decreases and the incoherent part increases. At the corresponding energies which depend on the phonon frequency, two dips in the elastic and two peaks in the inelastic conductance spectra appear. The reason is the absorption of the phonon by the electron in transition into inelastic channels.展开更多
We give a survey on the Berezin transform and its applications in operator theory. The focus is on the Bergman space of the unit disk and the Fock space of the complex plane. The Berezin transform is most effective an...We give a survey on the Berezin transform and its applications in operator theory. The focus is on the Bergman space of the unit disk and the Fock space of the complex plane. The Berezin transform is most effective and most successful in the study of Hankel and Toepltiz operators.展开更多
In this paper,we study unbounded complex symmetric Toeplitz operators on the Hardy space H^(2)(D) and the Fock space g^(2).The technique used to investigate the complex symmetry of unbounded Toeplitz operators is diff...In this paper,we study unbounded complex symmetric Toeplitz operators on the Hardy space H^(2)(D) and the Fock space g^(2).The technique used to investigate the complex symmetry of unbounded Toeplitz operators is different from that used to investigate the complex symmetry of bounded Toeplitz operators.展开更多
Let M be an approximately finite codimensional quasi-invariant subspace of the Fock space. This paper gives a formula to calculate the codimension of such spaces and uses this formula to study the structure of quasi-i...Let M be an approximately finite codimensional quasi-invariant subspace of the Fock space. This paper gives a formula to calculate the codimension of such spaces and uses this formula to study the structure of quasi-invariant subspaces of the Fock space. Especially, as one of applications, it is showed that the analogue of Beurling's theorem is not true for the Fock space L_a^2 in the case of n > 2.展开更多
We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-...We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-like numbers together with the general mutual transformation rule between normal and anti-normal orderings of operators.Further,the Q-and P-ordered forms of(QP)±m are also obtained by using an analogy method.展开更多
In the setting of Fock-Sobolev spaces of positive orders over the complex plane,Choe and Yang showed that if the one of the symbols of two commuting Toeplitz operators with bounded symbols is non-trivially radial,then...In the setting of Fock-Sobolev spaces of positive orders over the complex plane,Choe and Yang showed that if the one of the symbols of two commuting Toeplitz operators with bounded symbols is non-trivially radial,then the other must also be radial.In this paper,we extend this result to the Fock-Sobolev space of negative order using the Fock-type space with a confluent hyper geometric function.展开更多
In this paper we first introduce and investigate some special classes of nonlinear maps and get several useful results. Then, by using these results, we obtain analytic criteria for checking whether or not an operator...In this paper we first introduce and investigate some special classes of nonlinear maps and get several useful results. Then, by using these results, we obtain analytic criteria for checking whether or not an operator defined only on the exponential vectors of a symmetric Fock space becomes a Hilbert-Schmidt operator on the whole space. Additionally, as an application, we also get an analytic criterion for Hilbert-Schmidt operators on a Gaussian probability space through the Wiener-Ito-Segal isomorphism.展开更多
文摘Letϕbe a smooth radial weight that decays faster than the class Gaussian ones.We obtain certain estimates for the reproducing kernels and the Lp-estimates for solutions of theδ-equation on the weighted Fock spaces F_(ϕ)^(p)(1≤p≤∞),which extends the classical Hörmander Theorem.Furthermore,for a suitable f,we completely characterize the boundedness and compactness of the Hankel operator H_(f):F_(ϕ)^(p)→L^(q)(C,e^(qϕ(·))dm)for all possible 1≤p,q<∞and also characterize the Schatten-p class Hankel operator Hf from F_(ϕ)^(2)to L^(2)(C,E^(-2ϕ)dm) for all 0<p<∞. As an application, we give a complete characterization of the simultaneously bounded, compact and Schatten-p classes Hankel operators H_(f) and h_(f)^(-) on F_(ϕ)^(2).
基金supported by the NNSF of China(12071155)supported by the NNSF of China(11871170)+1 种基金the open project of Key Laboratory,school of Mathematical Sciences,Chongqing Normal University(CSSXKFKTM202002)supported by the Innovation Research for the Postgraduates of Guangzhou University(2020GDJC-D08)。
文摘In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equivalent characterizations for invertible Toeplitz operators Tψ,induced by positive bounded symbols φ on F^(2)_(φ).
基金Supported by National Natural Science Foundation of China(11471084,11301101,11971125)Young Innovative Talent Project of Department of Edcucation of Guangdong Province(2017KQNCX220)the Natural Research Project of Zhaoqing University(221622).
文摘In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson condition,bounded Toeplitz operators,compact Toeplitz operators,and Toeplitz operators in the Schatten-p class are all considered.
基金supported by the National Natural Science Foundation of China(No.11971340)。
文摘In this paper,the authors study the integral operator■induced by a kernel functionφ(z,·)∈F_α~∞between Fock spaces.For 1≤p≤∞,they prove that S_φ:F_α^(1)→F_α^(p)is bounded if and only if■where k_(a)is the normalized reproducing kernel of F_α^(2);and,S_φ:F_α^(1)→F_α^(p)is compact if and only if■When 1<q≤∞,it is also proved that the condition(?)is not sufficient for boundedness of S_φ:F_α^(q)→F_α^(p).In the particular case■with ■∈F^(2)_α,for 1≤q<p<∞,they show that S_φ:F^(p)_α→F^(q)_αis bounded if and only if■;for 1<p≤q<∞,they give sufficient conditions for the boundedness or compactness of the operator S^(q)_φ:F^(p)_α→F_α.
文摘In this paper,we characterize the boundedness and compactness of the block dual Toeplitz operators acting on the orthogonal complement of the Fock spaces,and the compactness of the finite sum of two dual Toeplitz operators products.The commutator and semi-commutator induced by the block dual Toeplitz operators are considered.
基金Supported by Sichuan Science and Technology Program (No.2022ZYD0010)。
文摘The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given.
基金supported by NSFC(Grant Nos.11301101,11271092 and 11471084)the Guangzhou Higher Education Science and Technology Project(Grant No.2012A018)
文摘In this paper, we discuss the Schatten-p class （0 〈 p≤∞ ） of Toeplitz operators on generalized Foek space with the symbol in positive Borel measure. It makes a great difference from other papers by using the estimates of the kernel and the weight together instead of separately estimating each other. We also get the equivalent conditions when a Toeplitz operator is in the Schatten-p class.
基金Supported by the National Natural Science Foundation of China(Grant No.12271134)Shanxi Scholarship Council of China(Grant No.2020-089)Program of Graduate Bilingual Curriculum Construction in Shanxi Normal University(Grant No.YJSSY201903).
文摘In this paper,cohyponormal weighted composition operators on the Fock space over C^(N)are characterized completely.We also consider a class of weighted composition operators on the Fock space over C^(N)which are both posinormal and coposinormal.As an application,we obtain the characterization of hyponormal,cohyponormal,posinormal and coposinormal composition operators on the Fock space over C^(N).
基金Supported by the National Natural Science Foundation of China(Grant Nos.1120127411471189)
文摘This paper studies a class of weighted composition operators and their spectrum on the Fock space. As an application, bounded self-adjoint, a class of complex symmetric weighted composition operators on the Fock space are characterized.
文摘Based on a new characterization of bounded and compact weighted compositionoperators on the Fock space obtained by Le T （Le T. Normal and isometricweighted composition operators on the Fock space. Bull. London. Math. Soc., 2014,46： 847-856）, this paper shows that a bounded weighted composition operator onthe Fock space is a Fredholm operator if and only if it is an invertible operator, andif and only if it is a nonzero constant multiple of a unitary operator. The result isvery different from the corresponding results on the Hardy space and the Bergmanspace.
基金Supported by the National Natural Science Foundation of China(Grant No.11771401)Shanxi Scholarship Council of China(Grant No.2020-089)Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(Grant No.20200019).
文摘In this paper,we study bounded(linear and anti-linear)weighted composition operators on the symmetric Fock space over a separable Hilbert space.The unitary and self-adjoint weighted composition operators are characterized completely.A class of normal weighted composition operators is considered.
基金Project supported by the Iranian Nanotechnology Initiativesupported by Shahrekord University through a research fund
文摘We study the effect of electron-phonon （e-ph） interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The model is constructed using Green＇s function and multi-channel techniques, taking into account the local and nonlocal e-ph interactions. Then, we examine the model for the gapless （simple chain） and gapped （PA-like nanowire） systems. The results show that the tunneling conductance is improved by the e-ph interaction in both local and nonlocal regimes, while for the resonance conductance, the coherent part mainly decreases and the incoherent part increases. At the corresponding energies which depend on the phonon frequency, two dips in the elastic and two peaks in the inelastic conductance spectra appear. The reason is the absorption of the phonon by the electron in transition into inelastic channels.
基金Research partially supported by NNSF of China(11720101003)NSF of Guangdong Province(2018A030313512)+1 种基金Key projects of fundamental research in universities of Guangdong Province(2018KZDXM034)STU Scientific Research Foundation(NTF17009).
文摘We give a survey on the Berezin transform and its applications in operator theory. The focus is on the Bergman space of the unit disk and the Fock space of the complex plane. The Berezin transform is most effective and most successful in the study of Hankel and Toepltiz operators.
基金partially supported by the National Natural Science Foundation of China(11771340)。
文摘In this paper,we study unbounded complex symmetric Toeplitz operators on the Hardy space H^(2)(D) and the Fock space g^(2).The technique used to investigate the complex symmetry of unbounded Toeplitz operators is different from that used to investigate the complex symmetry of bounded Toeplitz operators.
文摘Let M be an approximately finite codimensional quasi-invariant subspace of the Fock space. This paper gives a formula to calculate the codimension of such spaces and uses this formula to study the structure of quasi-invariant subspaces of the Fock space. Especially, as one of applications, it is showed that the analogue of Beurling's theorem is not true for the Fock space L_a^2 in the case of n > 2.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11804085)the Natural Science Foundation of Shandong Province, China (Grant No. ZR2017MEM012).
文摘We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-like numbers together with the general mutual transformation rule between normal and anti-normal orderings of operators.Further,the Q-and P-ordered forms of(QP)±m are also obtained by using an analogy method.
基金supported by NRF of Korea(Grant No.NRF-2020R1F1A1A01048601)supported by NRF of Korea(Grant No.NRF-2020R1I1A1A01074837)。
文摘In the setting of Fock-Sobolev spaces of positive orders over the complex plane,Choe and Yang showed that if the one of the symbols of two commuting Toeplitz operators with bounded symbols is non-trivially radial,then the other must also be radial.In this paper,we extend this result to the Fock-Sobolev space of negative order using the Fock-type space with a confluent hyper geometric function.
基金Supported by National Natural Science Foundation of China(10171035)Natural Science Foundation of Gansu Province(ZS021-A25-004-Z) NWNU-KJCXGC-212
文摘In this paper we first introduce and investigate some special classes of nonlinear maps and get several useful results. Then, by using these results, we obtain analytic criteria for checking whether or not an operator defined only on the exponential vectors of a symmetric Fock space becomes a Hilbert-Schmidt operator on the whole space. Additionally, as an application, we also get an analytic criterion for Hilbert-Schmidt operators on a Gaussian probability space through the Wiener-Ito-Segal isomorphism.
