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Slow light with electromagnetically induced transparency in cylindrical waveguide  [PDF]
Agus Muhamad Hatta,Ali A. Kamli,Ola A. Al-Hagan,Sergey A. Moiseev
Physics , 2014,
Abstract: Slow light with electromagnetically induced transparency (EIT) in the core of cylindrical waveguide (CW) for an optical fiber system containing three-level atoms is investigated. The CW modes are treated in the weakly guiding approximation which renders the analysis into manageable form. The transparency window and permittivity profile of the waveguide due to the strong pump field in the EIT scheme is calculated. For a specific permittivity profile of the waveguide due to EIT, the propagation constant of the weak signal field and spatial shape of fundamental guided mode are calculated by solving the vector wave equation using the finite difference method. It is found that the transparency window and slow light field can be controlled via the CW parameters. The reduced group velocity of slow light in this configuration is useful for many technological applications such as optical memories, effective control of single photon fields, optical buffer and delay line.
Phase modulation induced by cooperative effects in electromagnetically induced transparency  [PDF]
R. Fleischhaker,T. N. Dey,J. Evers
Physics , 2009, DOI: 10.1103/PhysRevA.82.013815
Abstract: We analyze the influence of dipole-dipole interactions in an electromagnetically induced transparency setup at high density. We show both analytically and numerically that the polarization contribution to the local field strongly modulates the phase of a weak pulse. We give an intuitive explanation for this local field induced phase modulation and show that it distinctively differs from the nonlinear self-phase modulation a strong pulse experiences in a Kerr medium.
Local Modulation of Double Electromagnetically Induced Transparency Spectrum
HOU Bang-Pin,WANG Shun-Jin,YU Wan-Lun,SUN Wei-Li,
侯邦品
,王顺金,余万伦,孙威立

中国物理快报 , 2007,
Abstract: The double electromagnetically induced transparency induced by two coupling fields can be realized in a fourlevel tripod-type atom. Such double transparency spectra can be locally modulated by using the weak coherent fields to perturb the coupling transitions. These investigations within this scheme can be independent of Doppler broadening by properly orienting these fieds.
Electromagnetically Induced Transparency and Slow Light with Optomechanics  [PDF]
Amir H. Safavi-Naeini,Thiago P. Mayer Alegre,Jasper Chan,Matt Eichenfield,Martin Winger,Qiang Lin,Jeffrey T. Hill,Darrick Chang,Oskar Painter
Physics , 2010, DOI: 10.1038/nature09933
Abstract: Controlling the interaction between localized optical and mechanical excitations has recently become possible following advances in micro- and nano-fabrication techniques. To date, most experimental studies of optomechanics have focused on measurement and control of the mechanical subsystem through its interaction with optics, and have led to the experimental demonstration of dynamical back-action cooling and optical rigidity of the mechanical system. Conversely, the optical response of these systems is also modified in the presence of mechanical interactions, leading to strong nonlinear effects such as Electromagnetically Induced Transparency (EIT) and parametric normal-mode splitting. In atomic systems, seminal experiments and proposals to slow and stop the propagation of light, and their applicability to modern optical networks, and future quantum networks, have thrust EIT to the forefront of experimental study during the last two decades. In a similar fashion, here we use the optomechanical nonlinearity to control the velocity of light via engineered photon-phonon interactions. Our results demonstrate EIT and tunable optical delays in a nanoscale optomechanical crystal device, fabricated by simply etching holes into a thin film of silicon (Si). At low temperature (8.7 K), we show an optically-tunable delay of 50 ns with near-unity optical transparency, and superluminal light with a 1.4 microseconds signal advance. These results, while indicating significant progress towards an integrated quantum optomechanical memory, are also relevant to classical signal processing applications. Measurements at room temperature and in the analogous regime of Electromagnetically Induced Absorption (EIA) show the utility of these chip-scale optomechanical systems for optical buffering, amplification, and filtering of microwave-over-optical signals.
Coupled cavities for enhancing the cross-phase modulation in electromagnetically induced transparency  [PDF]
T. Opatrny,D. -G. Welsch
Physics , 2000, DOI: 10.1103/PhysRevA.64.023805
Abstract: We propose an optical double-cavity resonator whose response to a signal is similar to that of an Electromagnetically Induced Transparency (EIT) medium. A combination of such a device with a four-level EIT medium can serve for achieving large cross-Kerr modulation of a probe field by a signal field. This would offer the possibility of building a quantum logic gate based on photonic qubits. We discuss the technical requirements that are necessary for realizing a probe-photon phase shift of Pi caused by a single-photon signal. The main difficulty is the requirement of an ultra-low reflectivity beamsplitter and to operate a sufficiently dense cool EIT medium in a cavity.
Electromagnetically Induced Transparency and Light Storage in an Atomic Mott Insulator  [PDF]
U. Schnorrberger,J. D. Thompson,S. Trotzky,R. Pugatch,N. Davidson,S. Kuhr,I. Bloch
Physics , 2009, DOI: 10.1103/PhysRevLett.103.033003
Abstract: We experimentally demonstrate electromagnetically induced transparency and light storage with ultracold 87Rb atoms in a Mott insulating state in a three dimensional optical lattice. We have observed light storage times of about 240 ms, to our knowledge the longest ever achieved in ultracold atomic samples. Using the differential light shift caused by a spatially inhomogeneous far detuned light field we imprint a "phase gradient" across the atomic sample, resulting in controlled angular redirection of the retrieved light pulse.
The Electromagnetically Induced Transparency in Mechanical Effects of Light  [PDF]
G. S. Agarwal,Sumei Huang
Physics , 2009, DOI: 10.1103/PhysRevA.81.041803
Abstract: We consider the dynamical behavior of a nanomechanical mirror in a high-quality cavity under the action of a coupling laser and a probe laser. We demonstrate the existence of the analog of electromagnetically induced transparency (EIT) in the output field at the probe frequency. Our calculations show explicitly the origin of EIT-like dips as well as the characteristic changes in dispersion from anomalous to normal in the range where EIT dips occur. Remarkably the pump-probe response for the opto mechanical system shares all the features of the Lambda system as discovered by Harris and collaborators.
Electromagnetically-induced transparency and light storing of a pair of pulses  [PDF]
A. Raczynski,J. Zaremba,S. Zielinska-Kaniasty
Physics , 2003, DOI: 10.1103/PhysRevA.69.043801
Abstract: Electromagnetically-induced transparency and light storing are studied in the case of a medium of atoms in a double Lambda configuration, both in terms of dark- and bright-state polatitons and atomic susceptibility. It is proven that the medium can be made transparent simultaneously for two pulses following their self-adjusting so that a condition for an adiabatic evolution has become fulfilled. Analytic formulas are given for the shapes and phases of the transmitted/stored pulses. The level of transparency can be regulated by adjusting the heights and phases of the control fields.
Diffuse light scattering dynamics under conditions of electromagnetically induced transparency  [PDF]
V. M. Datsyuk,I. M. Sokolov,D. V. Kupriyanov,M. D. Havey
Physics , 2006, DOI: 10.1103/PhysRevA.74.043812
Abstract: We show that, under conditions of electromagnetically induced transparency (EIT), a significant portion of the incident probe pulse can be transferred into Rayleigh and Raman scattering channels. The light scattered into the Rayleigh channel emerges from the sample with an EIT time delay. We show that a proper description of the probe light propagation in the sample should include, in the diffusion dynamics, a spin polariton generated by the two-photon EIT process. The results have important implications for studies of weak light localization, and for manipulation of single and few photon states in ultracold atomic gases.
Slow light of an amplitude modulated Gaussian pulse in electromagnetically induced transparency medium  [PDF]
Wenzhuo Tang,Bin Luo,Yu Liu,Hong Guo
Physics , 2009,
Abstract: The slow light effects of an amplitude modulated Gaussian (AMG) pulse in a cesium atomic vapor are presented. In a single-$\Lambda$ type electromagnetically induced transparency (EIT) medium, more severe distortion is observed for an AMG pulse than a Gaussian one. Using Fourier spectrum analysis, we find that the distortion, as well as the loss, is dominantly caused by linear absorption than dispersion. Accordingly, a compensation method is proposed to reshape the slow light pulse based on the transmission spectrum. In addition, we find a novel way to obtain simultaneous slow and fast light.
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