Limits...
Time Circular Birefringence in Time-Dependent Magnetoelectric Media.

Zhang RY, Zhai YW, Lin SR, Zhao Q, Wen W, Ge ML - Sci Rep (2015)

Bottom Line: The superposition of the two TCB modes causes the "time Faraday effect", namely the globally unified polarization axes rotate with time.If the wave-vector spectrum of a pulse mainly concentrates in the non-traveling-wave band, the pulse will be trapped with nearly fixed center while its intensity will grow rapidly.In addition, we propose an experimental scheme of using molecular fluid with external time-varying electric and magnetic fields both parallel to the direction of light to realize these phenomena in practice.

View Article: PubMed Central - PubMed

Affiliation: Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin, 300071, China.

ABSTRACT
Light traveling in time-dependent media has many extraordinary properties which can be utilized to convert frequency, achieve temporal cloaking, and simulate cosmological phenomena. In this paper, we focus on time-dependent axion-type magnetoelectric (ME) media, and prove that light in these media always has two degenerate modes with opposite circular polarizations corresponding to one wave vector , and name this effect "time circular birefringence" (TCB). By interchanging the status of space and time, the pair of TCB modes can appear simultaneously via "time refraction" and "time reflection" of a linear polarized incident wave at a time interface of ME media. The superposition of the two TCB modes causes the "time Faraday effect", namely the globally unified polarization axes rotate with time. A circularly polarized Gaussian pulse traversing a time interface is also studied. If the wave-vector spectrum of a pulse mainly concentrates in the non-traveling-wave band, the pulse will be trapped with nearly fixed center while its intensity will grow rapidly. In addition, we propose an experimental scheme of using molecular fluid with external time-varying electric and magnetic fields both parallel to the direction of light to realize these phenomena in practice.

No MeSH data available.


Related in: MedlinePlus

Illustration of time refraction, time reflection and time Faraday rotation for a linearly polarized light incident upon a time wave plate with time-dependent ME coefficient Θ = βt/μ1(t0 < t t1).At t0, the wave splits into a time refracted part and a time reflected part. The two parts are both elliptically polarized, but their major axes rotate with time. After the second interface t1, the polarization axes of the four outgoing waves have angular differences with respect to the polarization of the incident wave.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4556965&req=5

f1: Illustration of time refraction, time reflection and time Faraday rotation for a linearly polarized light incident upon a time wave plate with time-dependent ME coefficient Θ = βt/μ1(t0 < t t1).At t0, the wave splits into a time refracted part and a time reflected part. The two parts are both elliptically polarized, but their major axes rotate with time. After the second interface t1, the polarization axes of the four outgoing waves have angular differences with respect to the polarization of the incident wave.

Mentions: Just as spatial optical wave plate devices, we analyze light propagating in a “time wave plate” with piecewise medium parameters: ε0, μ0, Θ0 are constant when t < t0; ε1(t), μ1(t), Θ1(t) are some continuous functions when t0 < t < t1; ε2, μ2, Θ2 are also constant when t > t1, as shown in Fig. 1. For a linearly polarized incident wave with and , the wave will become the sum of the two TCB modes at t0. Moreover, there always exist two linearly independent solutions for Eq. (4) which are complex conjugates of each other: , then the general solution of Eq. (4) is their superposition: , and the two TCB states can be further separated as . It can be proved that the momentums of the two branches and are always in opposite directions, i.e. one branch always propagates along the incident direction (for convenience, let it be ), while the other (let it be ) is always along the opposite. As a result, and are exactly the “time refraction” and “time reflection” of the corresponding TCB modes at the time interface t0 (see the supplementary information for more discussions).


Time Circular Birefringence in Time-Dependent Magnetoelectric Media.

Zhang RY, Zhai YW, Lin SR, Zhao Q, Wen W, Ge ML - Sci Rep (2015)

Illustration of time refraction, time reflection and time Faraday rotation for a linearly polarized light incident upon a time wave plate with time-dependent ME coefficient Θ = βt/μ1(t0 < t t1).At t0, the wave splits into a time refracted part and a time reflected part. The two parts are both elliptically polarized, but their major axes rotate with time. After the second interface t1, the polarization axes of the four outgoing waves have angular differences with respect to the polarization of the incident wave.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556965&req=5

f1: Illustration of time refraction, time reflection and time Faraday rotation for a linearly polarized light incident upon a time wave plate with time-dependent ME coefficient Θ = βt/μ1(t0 < t t1).At t0, the wave splits into a time refracted part and a time reflected part. The two parts are both elliptically polarized, but their major axes rotate with time. After the second interface t1, the polarization axes of the four outgoing waves have angular differences with respect to the polarization of the incident wave.
Mentions: Just as spatial optical wave plate devices, we analyze light propagating in a “time wave plate” with piecewise medium parameters: ε0, μ0, Θ0 are constant when t < t0; ε1(t), μ1(t), Θ1(t) are some continuous functions when t0 < t < t1; ε2, μ2, Θ2 are also constant when t > t1, as shown in Fig. 1. For a linearly polarized incident wave with and , the wave will become the sum of the two TCB modes at t0. Moreover, there always exist two linearly independent solutions for Eq. (4) which are complex conjugates of each other: , then the general solution of Eq. (4) is their superposition: , and the two TCB states can be further separated as . It can be proved that the momentums of the two branches and are always in opposite directions, i.e. one branch always propagates along the incident direction (for convenience, let it be ), while the other (let it be ) is always along the opposite. As a result, and are exactly the “time refraction” and “time reflection” of the corresponding TCB modes at the time interface t0 (see the supplementary information for more discussions).

Bottom Line: The superposition of the two TCB modes causes the "time Faraday effect", namely the globally unified polarization axes rotate with time.If the wave-vector spectrum of a pulse mainly concentrates in the non-traveling-wave band, the pulse will be trapped with nearly fixed center while its intensity will grow rapidly.In addition, we propose an experimental scheme of using molecular fluid with external time-varying electric and magnetic fields both parallel to the direction of light to realize these phenomena in practice.

View Article: PubMed Central - PubMed

Affiliation: Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin, 300071, China.

ABSTRACT
Light traveling in time-dependent media has many extraordinary properties which can be utilized to convert frequency, achieve temporal cloaking, and simulate cosmological phenomena. In this paper, we focus on time-dependent axion-type magnetoelectric (ME) media, and prove that light in these media always has two degenerate modes with opposite circular polarizations corresponding to one wave vector , and name this effect "time circular birefringence" (TCB). By interchanging the status of space and time, the pair of TCB modes can appear simultaneously via "time refraction" and "time reflection" of a linear polarized incident wave at a time interface of ME media. The superposition of the two TCB modes causes the "time Faraday effect", namely the globally unified polarization axes rotate with time. A circularly polarized Gaussian pulse traversing a time interface is also studied. If the wave-vector spectrum of a pulse mainly concentrates in the non-traveling-wave band, the pulse will be trapped with nearly fixed center while its intensity will grow rapidly. In addition, we propose an experimental scheme of using molecular fluid with external time-varying electric and magnetic fields both parallel to the direction of light to realize these phenomena in practice.

No MeSH data available.


Related in: MedlinePlus