Results 41 to 50 of about 1,363,250 (192)

Propagation of light through small clouds of cold interacting atoms [PDF]

, 2015
We demonstrate experimentally that a cloud of cold atoms with a size comparable to the wavelength of light can induce large group delays on a laser pulse when the laser is tightly focused on it and is close to an atomic resonance.
Browaeys, A., Greffet, J. -J., Jennewein, S., Sortais, Y. R. P.   +3 more
core   +2 more sources

Elementary Negative Group Delay Filter Functions

Circuits, Systems, and Signal Processing
AbstractA theoretical study of the behavior of some elementary first- and second-order functions, which are suitable for realizing negative group delay, is performed in this work. As both the gain and phase responses are simultaneously considered, important derivations related to the actual bandwidth of operation are derived accompanied by useful ...
Julia Nako, Costas Psychalinos, Brent J. Maundy, Ahmed S. Elwakil   +3 more
openaire   +2 more sources

Negative Group Delay Theory of a Four-Port RC-Network Feedback Operational Amplifier

IEEE Access, 2019
An innovative negative group delay (NGD) theory based on a unity direct chain feedback (UDCF) circuit topology is developed in this paper. This NGD circuit is an active cell constituted by an operational amplifier in feedback with a four-port RC-network.
Fayu Wan, Taocheng Gu, Blaise Ravelo, Binhong Li, Jing Cheng, Qingyun Yuan, Junxiang Ge   +6 more
doaj   +1 more source

Design and Synthesis of Inductorless Passive Cell Operating as Stop-Band Negative Group Delay Function

IEEE Access, 2021
This paper develops an original circuit theory of unfamiliar stop-band (SB) negative group delay (NGD) topology. The proposed NGD topology is implemented without inductor component.
Mathieu Guerin, Yang Liu, Alexandre Douyere, George Chan, Fayu Wan, Sebastien Lallechere, Wenceslas Rahajandraibe, Blaise Ravelo   +7 more
doaj   +1 more source

Plasmonic-Dielectric Systems for High-Order Dispersionless Slow or Stopped Subwavelength Light [PDF]

, 2009
A material platform of multilayered surface-plasmon-dielectric-polariton systems is introduced, along with a new physical mechanism enabling simultaneous cancellation of group-velocity and attenuation dispersion to extremely high orders for subwavelength
Aristeidis Karalis, B. E. A. Saleh, G. P. Agrawal, J. D. Joannopoulos, Marin Soljačić, O. Svelto, S. A. Maier   +6 more
core   +1 more source

Band Pass Negative Group Delay demonstration on a VHF RLC parallel passive lumped circuit

Advanced Electromagnetics, 2022
This paper demonstrates the bandpass (BP) negative group delay (NGD) function on a passive RLC-parallel lumped network at Very High Frequencies (VHF). After the topological description of the RLC cell, the BP NGD analysis is introduced.
E. J. R. Sambatra, Y. C. Mombo Boussougou, Lucius Ramifidisoa, J.-P. Kouadio, S. Ngoho, A. Jaomiary, N. M. Murad   +6 more
doaj   +1 more source

Time for pulse traversal through slabs of dispersive and negative ($\epsilon$, $\mu$) materials

, 2007
The traversal times for an electromagnetic pulse traversing a slab of dispersive and dissipative material with negative dielectric permittivity ($\epsilon$) and magnetic permeability ($\mu$) have been calculated by using the average flow of ...
A. I. Talukder, Lipsa Nanda, R. Y. Chiao, S. Anantha Ramakrishna   +3 more
core   +1 more source

Intersexual conflict influences female reproductive success in a female-dispersing primate [PDF]

, 2019
In group-living mammals, individual efforts to maximize reproductive success result in conflicts and compromises between the sexes. Females utilize counterstrategies to minimize the costs of sexual coercion by males, but few studies have examined the ...
Breuer, T., Manguette, M., Parnell, R., Robbins, A., Robbins, M., Stokes, E.   +5 more
core   +2 more sources

A note on the bandwidth of negative group delay filters

International Journal of Circuit Theory and Applications
SummaryAn updated definition of group delay bandwidth in analog filters is introduced in this work. Unlike existing definitions, this new definition considers simultaneously the value of the group delay and filter gain, leading to minimized distortion in the filter output.
Julia Nako, Costas Psychalinos, Ahmed S. Elwakil, Brent J. Maundy   +3 more
openaire   +1 more source

Synthesis of RF Circuits with Negative Time Delay by Using LNA

Advanced Electromagnetics, 2013
A demonstration of the negative time-delay by using active circuit topologies with negative group delay (NGD) is described in this paper. This negative time delay is realized with two different topologies operating in base band and modulated frequencies.
B. Ravelo
doaj   +1 more source