相关论文: Low-distortion slow light using two absorption res…

We report an observation of a delayed all-optical routing/switching phenomenon based on ultraslow group velocity of light via nondegenerate four-wave mixing processes in a defected solid medium. Unlike previous demonstrations of enhanced…

We have analyzed the transmission properties of pulses through one-dimensional periodic structures in order to systematically explore the best conditions to achieve the maximum delay with the minimum possible distortion. In the absence of…

We study the propagation of light pulses in an absorbing medium when the frequency of their carrier coincides with a zero of the refractive index dispersion. Although slow light and, a fortiori, fast light are not expected in such…

We calculate the characteristics of ultraslow light in an inhomogeneously broadened medium. We present analytical and numerical results for the group delay as a function of power of the propagating pulse. We apply these results to explain…

Spectroscopy has attracted much attention in molecular detection, biomolecular identification, and chemical analysis for providing accurate measurement. However, it is almost unable to distinguish different sources with overlapped…

Lensless imaging is an elegant approach to high-resolution microscopy, which is rapidly gaining popularity in applications where imaging optics are problematic. However, current lensless imaging methods require objects to be placed within a…

We predict and experimentally demonstrate a new type of collective (cooperative) coupling effect where a disordered atomic ensemble absorbs light with a rise-time longer (i. e., at a rate slower) than what is dictated by single-atom…

In this paper, two-photon absorption resonance has been investigated . We studied this phenomenon in three-level system with common upper level, two lower long-life levels and two quasi-resonant laser fields with different frequency…

The ability to control the speed and polarisation of light pulses will allow for faster data flow in optical networks of the future. Optical delay and switching have been achieved using slow-light techniques in various media, including…

We investigate dispersion and absorption properties of a weak probe field in a four level atomic system through interacting dark resonances. We show that two narrow peaks appears in the optical spectra due to the presence of interacting…

Maximizing nonlinear light-matter interactions is a primary motive for compressing laser pulses to achieve ultrashort transform limited pulses. Here we show how, by appropriately shaping the pulses, resonant multiphoton transitions can be…

We derive the two-time linear response theory for out-of-equilibrium pumped systems, generic pump-probe delays and probe frequencies. Such a theory enormously simplifies the numerical calculations, for instance, of the optical conductivity…

It is shown theoretically that an optical bottle resonator with a nanoscale radius variation can perform a multi-nanosecond long dispersionless delay of light in a nanometer-order bandwidth with minimal losses. Experimentally, a 3 mm long…

In cognitive radio systems, secondary users can utilize multiple dispersed bands that are not used by primary users. In this paper, time delay estimation of signals that occupy multiple dispersed bands is studied. First, theoretical limits…

We theoretically study a novel method for all-optical delay of images based on backward four-wave mixing in composites containing metal nanoparticles. In this approach a delayed phase conjugate probe pulse is generated by the interaction of…

We demonstrate an all-optical delay line in hot cesium vapor that tunably delays 275 ps input pulses up to 6.8 ns and 740 input ps pulses up to 59 ns (group index of approximately 200) with little pulse distortion. The delay is made tunable…

Using numerical simulations of two-photon electronic absorption with femtosecond pulses in Na$_2$ we show that: i) it is possible to avoid the characteristic saturation or dumped Rabi oscillations in the yield of absorption by time-delaying…

In connection with the experiments recently achieved on doped crystals, biological samples, doped optical fibers and semiconductor heterostructures, we revisit the theory of the propagation of a pulse-modulated light in a saturable…

The linear susceptibility of an atomic sample is formally equivalent to the response of a RLC circuit. We use a ladder of lumped RLC circuits to observe an analogue of slow-light, a well-known phenomenon in atomic physics. We first…

We develop a method to control the group delay of electromagnetic waves continuously using a doubly resonant metasurface. The method is based on the dependences of i) the group velocity in a medium featuring two resonance lines on the…