Observation of Backward Pulse Propagation Through a Medium with a Negative Group Velocity

Gehring, George M.; Schweinsberg, Aaron; Barsi, Christopher; Kostinski, Natalie; Boyd, Robert W.

doi:10.1126/science.1124524

Cited by 236 publications

(133 citation statements)

References 27 publications

Supporting

Mentioning

125

Contrasting

Order By: Relevance

“…Near such electric-dipole transitions the permittivity of the material can be strongly modified, giving rise to a whole family of optical effects. For example, using electromagnetically induced transparency and related ideas, light can be slowed down, stopped, or even forced to move backward, and optical nonlinearities can be made large enough to be effective at the single-photon level [21][22][23][24][25][26][27][28]. Although these are exciting developments, it is important to note that these atomic physics experiments are not truly comparable to metamaterials work since there is negligible interaction with the magnetic field of light.…”

Section: Introductionmentioning

confidence: 99%

Coherent Magnetic Response at Optical Frequencies Using Atomic Transitions

et al. 2017

View full text Add to dashboard Cite

In optics, the interaction of atoms with the magnetic field of light is almost always ignored since its strength is many orders of magnitude weaker compared to the interaction with the electric field. In this article, by using a magnetic-dipole transition within the 4f shell of europium ions, we show a strong interaction between a green laser and an ensemble of atomic ions. The electrons move coherently between the ground and excited ionic levels (Rabi flopping) by interacting with the magnetic field of the laser. By measuring the Rabi flopping frequency as the laser intensity is varied, we report the first direct measurement of a magnetic-dipole matrix element in the optical region of the spectrum. Using density-matrix simulations of the ensemble, we infer the generation of coherent magnetization with magnitude 5.5 × 10 −3 A=m, which is capable of generating left-handed electromagnetic waves of intensity 1 nW=cm 2 . These results open up the prospect of constructing left-handed materials using sharp transitions of atoms.

show abstract

Section: Introductionmentioning

confidence: 99%

Coherent Magnetic Response at Optical Frequencies Using Atomic Transitions

et al. 2017

View full text Add to dashboard Cite

show abstract

“…For example, the applied coherent fields can eliminate absorption, enhance the index of refraction [8][9][10], induce chirality in nonchiral media [11], produce usually forbidden forward Brillouin scattering or strong coherent backward scattering in ultradispersive resonant media [12,13], slow down or speed up light pulses [14][15][16], provide the optical imaging beyond diffraction limit [17], and the optical analog of Stern-Gerlach experiment [18]. Optically controlled giant nonlinearities may generate nonlinear signals using single photons [19,20].…”

Section: Introductionmentioning

confidence: 99%

Ultradispersive adaptive prism based on a coherently prepared atomic medium

Sautenkov

Rostovtsev

et al. 2010

Phys. Rev. A

View full text Add to dashboard Cite

We have experimentally demonstrated an ultra-dispersive optical prism made from a coherently driven Rb atomic vapor. The prism possesses spectral angular dispersion that is 6 orders of magnitude higher than that of a prism made of optical glass; such angular dispersion allows one to spatially resolve light beams with different frequencies separated by a few kilohertz. The prism operates near the resonant frequency of atomic vapor and its dispersion is optically controlled by a coherent driving field.

show abstract

“…As a result, this approach is of limited use for real signal-processing applications, but is a good tool for investigating large velocity changes. An interesting study of the propagation in a negative-velocity regime under extreme fast-light conditions was performed using this approach, with step-by-step observation of a backward propagating pulse 29 .…”

Section: Special-fibre Approachesmentioning

confidence: 99%

Slow and fast light in optical fibres

2008

View full text Add to dashboard Cite

The ubiquitous role of optical fibres in modern photonic systems has stimulated research to realize slow and fast light devices directly in this close-to-perfect transmission line. Recent progress in developing optically controlled delays in optical fibres, operating under normal environmental conditions and at telecommunication wavelengths, has paved the way towards real applications for slow and fast light. This review presents the state-of-the-art research in this fascinating field and possible outcomes in the near future. The development of high-quality silica optical fibres with excellent transmission capabilities has directly contributed to the tremendous expansion of the global communication network. The success is due to their unrivalled low-loss performance (typically 50% of light is still present after a 15-km transmission distance), their wide bandwidth, which allows terabits per second of information to be transmitted over more than 1,000 km, and also their extremely low production cost. Realizing tunable delays for optical data signals directly in fibres, as well as integrating such devices into existing communication networks, is certainly a very attractive approach for optimizing the flow of data traffic in future networks. The approach may also enhance the capabilities of optical and microwave-on-optical-carrier signal processing. Given the limited possibilities for engineering the dispersion curve of standard single-mode fibres without creating complex photonic-crystal structures (see pages 448 and 465 of this issue 1,2 ), much research on fibre-based delays has been directed towards solutions based on spectral resonances to generate slow and fast light. The initial pioneering demonstrations of slow and fast light in various media all exploited narrow spectral resonances, typically created by electromagnetically induced transparency 3 or coherent population oscillation 4 . Narrow spectral resonances have a dramatic effect on optical propagation, as any sharp spectral change in the medium's transmission curve results in a steep quasi-linear variation of the effective refractive index with wavelength in the narrow spectral region near the resonance. This in turn results in a strong change in the group velocity at the exact centre of the resonance 5 . The velocity change is strongest for narrower spectral resonances (as explained in detail below) and for this reason, the early experiments were all carried out in special media, such as ultracold atomic gases or atomic transitions in a crystalline solid at a well-defined wavelength. Luc ThévenazWithin the resonance, the relationship between the change in the optical transmission and the delay can be determined as follows. The refractive-index change, Δn, as a function of the optical frequency, ν, is calculated using the Kramers-Kronig transformation, and the index change associated with the group velocity, Δn g , is then found using the relationship Δn g = Δn + ν(dΔn/dν) (ref. 5). Finally, the delay, ΔT, added to the normal transit time in the medium...

show abstract

Observation of Backward Pulse Propagation Through a Medium with a Negative Group Velocity

Cited by 236 publications

References 27 publications

Coherent Magnetic Response at Optical Frequencies Using Atomic Transitions

Coherent Magnetic Response at Optical Frequencies Using Atomic Transitions

Ultradispersive adaptive prism based on a coherently prepared atomic medium

Slow and fast light in optical fibres

Contact Info

Product

Resources

About