arXiv subjects

Jian-Zu Zhang

Publications and source records attributed to Jian-Zu Zhang.

18 recordsLinked to original sources

arXiv2019

Heisenberg Quantization in Physical Space Based on Established Experiments

It is clarified that Heisenberg quantization was proposed in empty space. Based on established experiments, the generalized Heisenberg quantization in physical space is obtained. Physical space quantization includes important new physics: Proving that physical space is noncommutative space; Exploring the existence of a non-zero minimal length scale, which leads to new space structures and the existence of the space minimal finite volume; Finding a new correlativity of the property of space with the motion status of the system: space non-commutativity is determined by the momentum non-commutativity.

quant-ph↗

arXiv2009

Deformed "Commutative" Chern - Simons System

Noncommutative Chern - Simons' system is non-perturbatively investigated at a full deformed level. A deformed "commutative" phase space is found by a non-canonical change between two sets of deformed variables of noncommutative space. It is explored that in the "commutative" phase space all calculations are similar to the case in commutative space. Spectra of the energy and angular momentum of the Chern - Simons' system are obtained at the full deformed level. The noncommutative-commutative correspondence is clearly showed. Formalism for the general dynamical system is briefly presented. Some subtle points are clarified.

hep-th↗

arXiv2009

Consistent Deformed Bosonic Algebra in Noncommutative Quantum Mechanics

In two-dimensional noncommutive space for the case of both position - position and momentum - momentum noncommuting, the consistent deformed bosonic algebra at the non-perturbation level described by the deformed annihilation and creation operators is investigated. A general relation between noncommutative parameters is fixed from the consistency of the deformed Heisenberg - Weyl algebra with the deformed bosonic algebra. A Fock space is found, in which all calculations can be similarly developed as if in commutative space and all effects of spatial noncommutativity are simply represented by parameters.

hep-th↗

arXiv2009

Angular Momentum of Supersymmetric Cold Rydberg Atoms

Semiunitary transformation is applied to discuss supersymmetrization of cold Rydberg atoms. In the limit of vanishing kinetic energy the lowest angular momentum of the supersymmetric cold Rydberg atom is $3\hbar/2$. A possible experimental verification is suggested.

hep-th↗

arXiv2009

Induced Fractional Zero-Point Angular Momentum for Charged Particles of the Bohm-Aharonov System by means of a "Spectator" Magnetic Field

An induced fractional zero-point angular momentum of charged particles by the Bohm-Aharonov (B-A) vector potential is realized via a modified combined trap. It explores a "spectator" mechanism in this type of quantum effects: In the limit of the kinetic energy approaching one of its eigenvalues the B-A vector potential alone cannot induce a fractional zero-point angular momentum at quantum mechanical level in the B-A magnetic field-free region; But when there is a "spectator" magnetic field the B-A vector potential induces a fractional zero-point angular momentum. The "spectator" does not contribute to such a fractional angular momentum, but plays essential role in guaranteeing non-trivial dynamics at quantum mechanical level in the required limit. This "spectator" mechanism is significant in investigating the B-A effects and related topics in both aspects of theory and experiment.

quant-ph↗

arXiv2009

Test of Quantum Effects of Spatial Noncommutativity using Modified Electron Momentum Spectroscopy

The possibility of testing spatial noncommutativity by current experiments on normal quantum scales is investigated. For the case of both position-position and momentum-momentum noncommuting spectra of ions in crossed electric and magnetic fields are studied in the formalism of noncommutative quantum mechanics. In a limit of the kinetic energy approaching its lowest eigenvalue this system possesses non-trivial dynamics. Signals of spatial noncommutativity in the angular momentum are revealed. They are within limits of the measurable accuracy of current experiments. An experimental test of the predictions using a modified electron momentum spectrum is suggested. The related experimental sensitivity and subtle points are discussed. The results are the first step on a realizable way towards a conclusive test of spatial noncommutativity.

quant-ph↗

arXiv2008

Noiseless Quantum Transmission of Information via Aharonov - Bohm Effect

The possibility of quantum transmission of information via the induced fractional angular momentum by the Aharonov - Bohm vector potential is revealed. Its special advantage is that it is noiseless: Stray magnetic fields of environments influence the energy spectrum of the ion, but cannot contribute the fractional angular momentum to cause noise.

quant-ph↗

arXiv2007

Induced Fractional Zero-Point Canonical Angular Momentum on Charged Particles of Aharonov - Bohm Vector Potential and "Spectator" Magnetic Field

The induced fractional zero-point canonical angular momentum on charged particles by the Aharonov - Bohm (AB) vector potential is realized via modified combined traps. It explores new features for this type of quantum effects: In a limit of vanishing mechanical kinetic energy the AB vector potential alone cannot induce a fractional zero-point canonical angular momentum on charged particles at the quantum mechanical level in the AB magnetic field-free region; But for the case of the AB vector potential with another one of a "spectator" magnetic field the AB vector potential induces a fractional zero-point canonical angular momentum in the same limit. The "spectator" one does not contribute to such a fractional zero-point quantity, but plays essential role in guaranteeing non-trivial dynamics survived in this limit at the quantum mechanical level. These results are significance in investigations of the AB effects and related fields for both theories and experiments.

quant-ph↗

arXiv2007

A Constraint between Noncommutative Parameters of Quantum Theories in Noncommutative Space

In two-dimensional noncommutive space for the case of both position - position and momentum - momentum noncommuting, a constraint between noncommutative parameters is investigated. The related topic of guaranteeing Bose - Einstein statistics in noncommutive space in the general case are elucidated: Bose - Einstein statistics is guaranteed by the deformed Heisenberg - Weyl algebra itself, independent of dynamics. A special character of a dynamical system is represented by a constraint between noncommutative parameters. The general feature of the constraint for any system is a direct proportionality between noncommutative parameters with a proportional coefficient depending on characteristic parameters of the system under study. The constraint for a harmonic oscillator is illustrated.

quant-ph↗

arXiv2006

Un-equivalency Theorem between Deformed and undeformed Heisenberg-Weyl's Algebras

Two fundamental issues about the relation between the deformed Heisenberg-Weyl algebra in noncommutative space and the undeformed one in commutative space are elucidated. First the un-equivalency theorem between two algebras is proved: the deformed algebra related to the undeformed one by a non-orthogonal similarity transformation is explored; furthermore, non-existence of a unitary similarity transformation which transforms the deformed algebra to the undeformed one is demonstrated. Secondly the uniqueness of realizing the deformed phase space variables via the undeformed ones is elucidated: both the deformed Heisenberg-Weyl algebra and the deformed bosonic algebra should be maintained under a linear transformation between two sets of phase space variables which fixes that such a linear transformation is unique. Elucidation of this un-equivalency theorem has basic meaning both in theory and experiment.

hep-th↗

arXiv2006

Searching for Effects of Spatial Noncommutativity via Chern-Simons' Processes

The possibility of testing spatial noncommutativity in the case of both position-position and momentum-momentum noncommuting via a Chern-Simons' process is explored. A Chern-Simons process can be realized by an interaction of a charged particle in special crossed electric and magnetic fields, in which the Chern-Simons term leads to non-trivial dynamics in the limit of vanishing kinetic energy. Spatial noncommutativity leads to the spectrum of the orbital angular momentum possessing fractional values. Furthermore, in both limits of vanishing kinetic energy and subsequent vanishing magnetic field, the Chern-Simons term leads to this system having non-trivial dynamics again, and the dominant value of the lowest orbital angular momentum being $\hbar/4$, which is a clear signal of spatial noncommutativity. An experimental verification of this prediction by a Stern-Gerlach-type experiment is suggested.

hep-ph↗

arXiv2006

Constraint on Quantum Gravitational Well in Noncommutative Space

In two-dimensional noncommutive space for the case of both position-position and momentum-momentum noncommuting, the constraint between noncommutative parameters on the quantum gravitational well is investigated. The related topic of guaranteeing Bose-Einstein statistics in the general case are elucidated: Bose-Einstein statistics is guaranteed by the deformed Heisenberg-Weyl algebra itself, independent of dynamics. A special feature of a dynamical system is represented by a constraint between noncommutative parameters. Such a constraint is fixed by dynamical considerations. The general feature of the constraint is a direct proportionality between noncommutative parameters with a coefficient composed by a product of characteristic parameters of the considered system. The constraint on the quantum gravitational well is obtained, and is applied to estimate the upper bound of the momentum-momentum noncommutative parameter from the experimental upper bound of the position-position noncommutative parameter.

hep-th↗

arXiv2006

Quantum Anomaly Dissociation of Quasibound States Near the Saddle-Point Ionization Limit of a Rydberg Electron in Crossed Electric and Magnetic Fields

In the combination of crossed electric and magnetic fields and the Coulomb field of the atomic nucleus the spectrum of the Rydberg electron in the vicinity of the Stark saddle-point are investigated at a quantum mechanical level. The results expose a quantum anomaly dissociation: quasibound states near and above the saddle-point ionization limit predicted at the semi-classical level disappear at a quantum mechanical level.

physics.class-ph↗

arXiv2006

Un-equivalency Theorem of Deformed Heisenberg-Weyl's Algebra in Noncommutative Space

An extensively tacit understandings of equivalency between the deformed Heisenberg-Weyl algebra in noncommutative space and the undeformed Heisenberg-Weyl algebra in commutative space is elucidated. Equivalency conditions between two algebras are clarified. It is explored that the deformed algebra related to the undeformed one by a non-orthogonal similarity transformation. Furthermore, non-existence of a unitary similarity transformation which transforms the deformed algebra to the undeformed one is demonstrated. The un-equivalency theorem between the deformed and the undeformed algebras is fully proved. Elucidation of this un-equivalency theorem has basic meaning both in theory and practice.

quant-ph↗

arXiv2005

Searching for effects of Spatial Noncommutativity via a Penning Trap

The possibility of testing spatial noncommutativity via a Penning trap is explored. The case of both space-space and momentum-momentum noncommuting is considered. Spatial noncommutativity leads to the spectrum of the orbital angular momentum of a Penning trap possessing fractional values, and in the limits of vanishing kinetic energy and subsequent vanishing magnetic field, this system has non-trivial dynamics. The dominant value of the lowest orbital angular momentum is $\hbar/4$, which is a clear signal of spatial noncommutativity. An experimental verification of this prediction by a Stern-Gerlach-type experiment is suggested.

hep-ph↗

arXiv2005

Coherent States of the Deformed Heisenberg-Weyl Algebra in Noncommutative Space

In two-dimensional space a subtle point that for the case of both space-space and momentum-momentum noncommuting, different from the case of only space-space noncommuting, the deformed Heisenberg-Weyl algebra in noncommutative space is not completely equivalent to the undeformed Heisenberg-Weyl algebra in commutative space is clarified. It follows that there is no well defined procedure to construct the deformed position-position coherent state or the deformed momentum-momentum coherent state from the undeformed position-momentum coherent state. Identifications of the deformed position-position and deformed momentum-momentum coherent states with the lowest energy states of a cold Rydberg atom in special conditions and a free particle, respectively, are demonstrated.

hep-th↗

arXiv2004

Deformed Two-Photon Squeezed States in Noncommutative Space

Recent studies on non-perturbation aspects of noncommutative quantum mechanics explored a new type of boson commutation relations at the deformed level, described by deformed annihilation-creation operators in noncommutative space. This correlated boson commutator correlates different degrees of freedom, and shows an essential influence on dynamics. This paper devotes to the development of formalism of deformed two-photon squeezed states in noncommutative space. General representations of deformed annihilation-creation operators and the consistency condition for the electromagnetic wave with a single mode of frequency in NC space are obtained. Two-photon squeezed states are studied. One finds that variances of the dimensionless hermitian quadratures of the annihilation operator in one degree of freedom include variances in the other degree of freedom. Such correlations show the new feature of spatial noncommutativity and allow a deeper understanding of the correlated boson commutator.

hep-th↗

arXiv2001

Supersymmetry in Quantum Mechanics of Colored Particles

The role of supercharge operators is studied in the case of a Dirac particle moving in a constant chromomagnetic field. The Hamiltonian is factorised and the ground state wave function in the case of unbroken supersymmetry is determined.

hep-th↗