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Related papers: Pushing the limits of negative group velocity

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Ultrafast lasers ($< 500$ fs) have enabled laser-matter interactions at intensities exceeding $10^{18} \rm{Wcm}^{-2}$ with only millijoules of laser energy. However, as pulse durations become shorter, larger spectral bandwidths are…

We present a fast phase gate scheme that is experimentally achievable and has an operation time more than two orders of magnitude faster than current experimental schemes for low numbers of pulses. The gate time improves with the number of…

Quantum Physics · Physics 2013-04-10 C. D. B. Bentley , A. R. R. Carvalho , D. Kielpinski , J. J. Hope

We observed periodic optical pulses from an Er:YSO crystal during irradiating with an continuous-wave excitation laser. We refer to this new phenomenon as "periodic super-radiance". This periodicity can be understood qualitatively by a…

Rapid emergence of smart mobility necessitates high-volume bursty data transmission over a single link between a target vehicle and its designated edge computing-enabled Base Station (BS) or Roadside Unit (RSU), which must be completed…

Information Theory · Computer Science 2026-03-04 Qianyao Ren , Qingxiao Huang , Yiqin Deng , Xianhao Chen , Phone Lin , Yuguang Fang

We investigated the structural evolution and optical properties of beta-Ga2O3 crystals implanted with different rare-earth (RE) ions using channeling Rutherford Backscattering Spectrometry, Positron Annihilation, Photoluminescence, and…

Reconfigurable Intelligent Surfaces (RISs) exhibit promising enhancements in coverage and data rates for wireless communication systems, particularly in the context of 5G and beyond. This paper introduces a novel approach by focusing on the…

Systems and Control · Electrical Eng. & Systems 2024-02-09 Jianan Zhang , Rujing Xiong , Junshuo Liu , Tiebin Mi , Robert Caiming Qiu

We present a detailed semiclassical study on the propagation of a pair of optical fields in resonant media with and without adiabatic approximation. In the case of near and on resonance excitation, we show detailed calculation, both…

Quantum Physics · Physics 2009-11-07 M. G. Payne , L. Deng , Chris Schmitt , Shannon Anderson

Ultrashort high-energy pulses at wavelengths longer than 1 $\mu$m are nowadays desired for a vast variety of applications in ultrafast and strong-field physics. To date, the main answer to the wavelength tunability for energetic, broadband…

The propagation of a probe laser field in a cavity optomechanical system with a Bose-Einstein condensate is studied. The transmission properties of the system are investigated and it is shown that the group velocity of the probe pulse field…

Quantum Gases · Physics 2016-02-17 S. Hamide Kazemi , Saeed Ghanbari , Mohammad Mahmoudi

Non-Hermitian systems with their spectral degeneracies known as exceptional points (EPs) have been explored for lasing, controlling light transport, and enhancing a sensor s response. A ring resonator can be brought to an EP by controlling…

Optics · Physics 2023-05-09 Hwaseob Lee , Ali Kecebas , Feifan Wang , Lorry Chang , Sahin K. Ozdemir , Tingyi Gu

Achieving low-latency time-reversal of broadband radiofrequency signals is crucial for reliable communications in dynamic, uncontrolled environments. However, existing approaches are either digitally assisted -- making broadband extension…

Optics · Physics 2025-08-07 Thomas Llauze , Anne Louchet-Chauvet

Rare-earth ions are promising solid state systems to build light-matter interfaces at the quantum level. This relies on their potential to show narrow optical homogeneous linewidths or, equivalently, long-lived optical quantum states. In…

Since the advent of chirped pulse amplification1 the peak power of lasers has grown dramatically and opened the new branch of high field science, delivering the focused irradiance, electric fields of which drive electrons into the…

The paper demonstrates that negative refractive index can be achieved via tuning the tunneling rate between a double quantum dots(QDs) system by applying a bias voltage, and a pulsed laser. As the bias voltage being changed, the refraction…

Optics · Physics 2024-02-08 Shun-Cai Zhao , Xiao-fan Qian , Ya-Ping Zhang , Yong-An Zhang

We investigate the different facets of ion acceleration by a relativistically intense circularly polarized laser pulse interacting with thin near-critical density plasma targets. Our simulations establish that plasma density gradient and…

Plasma Physics · Physics 2023-07-28 Shivani Choudhary , Sudipta Mondal , Daniele Margarone , Subhendu Kahaly

We have succeeded in observing ultraslow propagation of squeezed vacuum pulses with electromagnetically induced transparency. Squeezed vacuum pulses (probe lights) were incident on a laser cooled 87Rb gas together with an intense coherent…

The shape of an RF pulse is distorted upon propagating through an X-band accelerator structure due to dispersive effects. This distortion together with beam loading introduce energy spread between 192 bunches. In order to minimize this…

Accelerator Physics · Physics 2008-11-26 R. M. Jones , V. A. Dolgashev , R. H. Miller , C. Adolphsen , J. W. Wang

Reflection at relativistically moving plasma mirrors is a well-known approach for frequency conversion as an alternative to nonlinear techniques. A key issue with plasma mirrors is the need for a high carrier concentration, of order 10^21…

The fundamental performance metrics of an intelligent reflective surface (IRS)-aided wireless system are presented. By optimizing the IRS phase-shift matrix, the received signal-to-noise ratio (SNR) is maximized at the destination in the…

Signal Processing · Electrical Eng. & Systems 2020-10-26 Dulaj Gunasinghe , Dhanushka Kudathanthirige , Gayan Amarasuriya Aruma Baduge

To obtain the most accurate pulse arrival times from radio pulsars, it is necessary to correct or mitigate the effects of the propagation of radio waves through the warm and ionised interstellar medium. We examine both the strength of…

Instrumentation and Methods for Astrophysics · Physics 2016-11-15 R. M. Shannon , J. M. Cordes