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Jian Qi Shen

Publications and source records attributed to Jian Qi Shen.

At least 19 recordsLinked to original sources
arXiv2019

Non-Abelian gauge field optics

The concept of gauge field is a cornerstone of modern physics and the synthetic gauge field has emerged as a new way to manipulate particles in many disciplines. In optics, several schemes of Abelian synthetic gauge fields have been proposed. Here, we introduce a new platform for realizing synthetic SU(2) non-Abelian gauge fields acting on two-dimensional optical waves in a wide class of anisotropic materials and discover novel phenomena. We show that a virtual non-Abelian Lorentz force arising from material anisotropy can induce light beams to travel along Zitterbewegung trajectories even in homogeneous media. We further design an optical non-Abelian Aharonov-Bohm system which results in the exotic spin density interference effect. We can extract the Wilson loop of an arbitrary closed optical path from a series of gauge fixed points in the interference fringes. Our scheme offers a new route to study SU(2) gauge field related physics using optics.

physics.optics↗
arXiv2008

Interactions between Multipolar Nuclear Transitions and Gravitational Waves

Interactions between multipolar nuclear transitions and gravitational waves (GWs) are theoretically investigated. Two nonclassical scenarios of the GW detection are suggested. We demonstrate in this report that the long-lived Moessbauer nuclides of multipolar transitions are suitable transducers to detect the impinging GWs. Shape deformation and spin flip of nucleus are derived from the Hamiltonian with gravity interaction. The GWs generate a nuclear quadrupole deformation in analogy with the Stark effect, of which the electric field generates the dipole deformation of electron orbits. Likewise in analogy with the nuclear magnetic resonance that the rotating radio-frequency field flips the nuclear spin, the GWs flip the nuclear spin by the resonant helicity-rotation-gravity coupling. The high energy states of the quadrupole deformation in heavy nuclides can dramatically speed up the multipolar transitions, which may be important for the GW detection particularly in the low frequency band, ranging from 100 nHz to 1 Hz.

gr-qc↗
arXiv2005

Lorentz, Edwards transformations and the principle of permutation invariance

The Lorentz transformation is derived without the postulate of the universal limiting speed, and the general Edwards transformation is obtained by using the principle of permutation invariance (covariance). It is shown that the existences of the one-way universal limiting speed (in the Lorentz transformation) and the constancy of the two-way average speed of light (in the Edwards transformation) are the necessary consequences of the principle of permutation invariance that is consistent with the postulate of relativity. The connection between the Edward transformation and the general coordinate transformation is discussed, and based on this, we find that the physical meaning of the Edward parameter, which indicates the anisotropy of the speed of light, is a gravitomagnetic potential of the spacetime.

physics.class-ph↗
arXiv2005

Nonanalytic metric in the presence of gravitomagnetic monopoles

The nonanalytic property of metric resulting from the presence of gravitomagnetic monopoles is considered. The curvature tensors, dual curvature tensors, dual Einstein tensor (and hence the gravitational field equation of gravitomagnetic matter) expressed in terms of nonanalytic metric are analyzed. It is shown that the spinor gravitomagnetic monopole may be one of the potential origins of the cosmological constant. An alternative approach to the cosmological constant problem is thus proposed based on the concept of gravitomagnetic monopole.

gr-qc↗
arXiv2004

Berry's phase at quantum vacuum level

The quantum vacuum contribution to Berry's geometric phase of photon fields inside a noncoplanarly curved (coiled) fiber is considered by means of the second-quantization formulation. It is shown that the quantum vacuum Berry's phases of left- and right-handed circularly polarized light have the equal magnitudes but opposite signs, and are therefore eliminated entirely by each other. In order to realize such a novel vacuum effect, a scheme to separate the quantum vacuum Berry's phase of one polarized light from another by using the chiral medium fiber is suggested. We think the present study might be the first treatment for the time evolution of vacuum zero-point energy.

quant-ph↗
arXiv2004

Propagation of atomic matter waves inside an atom wave guide

The phenomenological description of propagation of atomic matter waves inside a curved atom wave guide is presented based on the effective action principle. The evolutions in both temporal and spatial domains for the atomic matter wave in the presence of guiding potential fields (classical and quantized) are considered. The coherent control of three-level atomic matter waves in a wave guide by an external controlling light is briefly discussed. The concepts of {\it atomic matter-wave bandgap structure} in a spatially periodic guiding field ({\it e.g.}, the interior potential of carbon peapod which can trap both atoms and light) and {\it optical lattice bandgap medium} are suggested.

quant-ph↗
arXiv2004

The supersymmetric Pegg-Barnett oscillator

The su$(n)$ Lie algebraic structure of the Pegg-Barnett oscillator that possesses a finite-dimensional number-state space is demonstrated. The supersymmetric generalization of Pegg-Barnett oscillator is suggested. It is shown that such a supersymmetric Pegg-Barnett oscillator may have some potential applications, {\it e.g.}, the mass spectrum of the charged leptons.

quant-ph↗
arXiv2004

How to realize a negative refractive index material at the atomic level in an optical frequency range

The theoretical mechanism for realizing the negative refractive index with {\it electromagnetically induced transparency} (EIT) is studied. It is shown that in a three-level dense atomic gas, there is a frequency band in which the EIT medium will exhibit simultaneously negative electric permittivity and magnetic permeability in the optical frequency range, and the atomic gas thus becomes a left-handed material. The expressions for the electric permittivity and the magnetic permeability for the probe frequency is presented. One of the remarkable features of the present novel scheme is such that the obtained EIT left-handed material is {\it isotropic} and may therefore have some potentially important applications in the development of new techniques in quantum optics.

cond-mat.mtrl-sci↗
arXiv2004

On the quantum vacuum contribution to the momentum of dielectric media

More recently, Feigel has considered the quantum vacuum contribution to the momentum of electromagnetic media. However, in Feigel's treatment he did not take into account the relativistic transformation of the optical constants (electric permittivity and magnetic permeability) of moving media. Here it is shown that the effect arising from such a transformation will also provide a quantum vacuum contribution to the velocity of media, in addition to the one derived by Feigel himself.

quant-ph↗
arXiv2004

Aharonov-Carmi effect and energy shift of valency electrons in rotating C_{60} molecules

It is shown that the valency electrons in rapidly rotating C_{60} molecules acquire an Aharonov-Carmi (A-C) phase shift, which is proportional to the molecular angular velocity flux enclosed by the matter wave of valency electrons on the C_{60} molecular shell. The energy shift of the valency electrons due to both the molecular rapid rotation and the molecular A-C phase shift is calculated.

cond-mat.other↗
arXiv2004

A note: graviton spin, gravitomagnetic fields and self-interaction of non-inertial frame of reference

Three weak gravitational effects associated with the gravitomagnetic fields are taken into account in this paper: (i) we discuss the background Lorentz transformation and gauge transformation in a linearized gravity theory, and obtain the expression for the spin of gravitational field by using the canonical procedure and Noether theorem; (ii) we point out that by using the coordinate transformation from the fixed frame to the rotating frame, it is found that the nature of Mashhoon's spin-rotation coupling is in fact an interaction between the gravitomagnetic moment of a spinning particle and the gravitomagnetic fields. The fact that the rotational angular velocity of a rotating frame can be viewed as a gravitomagnetic field is demonstrated; (iii) a purely gravitational generalization of Mashhoon's spin-rotation coupling, i.e., the interaction of the graviton spin with the gravitomagnetic fields is actually a self-interaction of the spacetime (gravitational fields). In the present paper, we will show that this self-interaction will also arise in a non-inertial frame of reference itself: specifically, a rotating frame that experiences a fluctuation of its rotational frequency (i.e., the change in the rotational angular frequency) will undergo a weak self-interaction. The self-interaction of the rotating frame, which can also be called the self-interaction of the spacetime of the rotating frame, is just the non-inertial generalization of the interaction of the graviton spin with the gravitomagnetic fields.

gr-qc↗
arXiv2004

The purely gravitational generalization of spin-rotation couplings

The nature of Mashhoon's spin-rotation coupling is the interaction between a particle spin (gravitomagnetic moment) and a gravitomagnetic field. Here we will consider the coupling of graviton spin to the weak gravitomagnetic fields by analyzing the Lagrangian density of weak gravitational field, and hence study the purely gravitational generalization of Mashhoon's spin-rotation couplings.

gr-qc↗
arXiv2004

The resemblances in mathematical structures between the optical constants of artificial electromagnetic media and some physical phenomena in field theory

This paper demonstrates that there is much similarity in the mathematical formalisms between the optical constants of artificial electromagnetic media (such as chiral media, left-handed media, photonic crystals and EIT media) and some physical phenomena in field theory, including general relativity, quantum mechanics, energy band theory, etc. The significance of such comparisons lies in that: (i) the unification in mathematical descriptions shows that many physical phenomena and effects, which seem to have no connections between them, actually share almost the same mathematical structures; (ii) it can provide clue to us on suggesting more new effects which is similar in mathematical descriptions to the familiar phenomena in other areas.

physics.ed-ph↗
arXiv2004

Automatical generation of nonadiabatic conditional geometric phase shift via a noncoplanar fiber system

A new scheme of realizing the nonadiabatic conditional geometric phase shift via a noncoplanar (and coiled) fiber system is presented in this Letter. It is shown that the effective Hamiltonian that describes the interaction of polarized photons with the fiber medium is just the Wang-Keiji type of Hamiltonian. This, therefore, means that the coiled fiber system may be an ideal implementation of realizing the nonadiabatic geometric phase gates for the topological quantum computation. The remarkable feature of the present method is that it can automatically meet the conditions and requirements proposed in the Wang-Keiji scheme: (i) in the coiled fiber system, the dynamical phase of photon wavefunction caused by the interaction Hamiltonian automatically vanishes; (ii) the Wang-Keiji requirement for the parameters in the Wang-Keiji Hamiltonian can be exactly satisfied automatically in the fiber system; (iii) the conditional initial state can be easily achieved by manipulating the initial wave vector of polarized photons. Due to these three advantages, the coiled fiber system may be a potentially practical way of achieving the nonadiabatic conditional geometric phase shift (and hence the nonadiabatic geometric quantum gates).

quant-ph↗
arXiv2004

The evolution of atomic matter waves inside an atom fiber

A phenomenological description of time evolution of atomic matter waves inside a spiral shaped atomic-wave guide is presented in this report. We study three related topics: (i) the effective Hamiltonian and the time-development equation governing the matter waves; (ii) wavefunctions describing the matter waves in the noncoplanar atom guide; (iii) showing that such wavefunctions obtained is just the eigenstates of the atomic momentum operator. It is believed that both the idea and the results presented here may have relevance to some fundamental problems of atom optics.

quant-ph↗
arXiv2004

The Pegg-Barnett oscillator and its supersymmetric generalization

The oscillator algebra of Pegg-Barnett (P-B) oscillator with a finite-dimensional number-state space is investigated in this note. It is shown that the Pegg-Barnett oscillator possesses the su($n$) Lie algebraic structure. Additionally, we suggest a so-called supersymmetric P-B oscillator and discuss the related topics such as the algebraic structure and particle occupation number of supersymmetric P-B oscillator.

quant-ph↗