A5063584977- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Quantum Mechanics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Mechanical and Optical Resonators
- Quantum Computing Algorithms and Architecture
- Laser-Matter Interactions and Applications
- Photonic and Optical Devices
- Orbital Angular Momentum in Optics
- Atomic and Subatomic Physics Research
- Random lasers and scattering media
- Advanced Fiber Laser Technologies
- Plasmonic and Surface Plasmon Research
- Advanced Thermodynamics and Statistical Mechanics
- Quantum Electrodynamics and Casimir Effect
- Spectroscopy and Quantum Chemical Studies
- Photorefractive and Nonlinear Optics
- Photonic Crystals and Applications
- Quantum and electron transport phenomena
- Laser Design and Applications
- Advanced Fluorescence Microscopy Techniques
- Experimental and Theoretical Physics Studies
- Neural Networks and Reservoir Computing
- Force Microscopy Techniques and Applications
- Metamaterials and Metasurfaces Applications
Texas A&M University
2016-2025
Mitchell Institute
2017-2025
Huazhong University of Science and Technology
2017-2022
University of California, Irvine
2020
Bar-Ilan University
2020
Zhejiang University
2018
Tsinghua University
2017
Beijing Computational Science Research Center
2011-2016
King Abdulaziz City for Science and Technology
2014-2015
COMSATS University Islamabad
2006-2014
We present here a quantum Carnot engine in which the atoms heat bath are given small bit of coherence. The induced coherence becomes vanishingly high-temperature limit at we operate and is essentially thermal. However, phase phi, associated with atomic coherence, provides new control parameter that can be varied to increase temperature radiation field extract work from single bath. deep physics behind second law thermodynamics not violated; nevertheless, has certain features possible...
We provide a class of inequalities whose violation shows the presence entanglement in two-mode systems. initially consider observables that are quadratic mode creation and annihilation operators find conditions under which state is entangled. Further examination allows us to formulate additional for detecting entanglement. conclude by showing how methods used here can be extended systems more than two modes.
Conventional spectroscopy uses classical light to detect matter properties through the variation of its response with frequencies or time delays.Quantum opens up new avenues for by utilizing parameters quantum state as novel control knobs and photon statistics coupling matter.This Roadmap article focuses on using a powerful sensing spectroscopic tool reveal information about complex molecules that is not accessible light.It aims at bridging optics communities which normally have opposite...
We consider a two-photon correlated emission laser as source of an entangled radiation with large number photons in each mode. The system consists three-level atomic schemes inside doubly resonant cavity. study the dynamics this presence cavity losses, concluding that creation states photon numbers up to tens thousands seems achievable.
Airborne contaminants, e.g., bacterial spores, are usually analyzed by time-consuming microscopic, chemical, and biological assays. Current research into real-time laser spectroscopic detectors of such contaminants is based on resonance fluorescence. The present approach derives from recent experiments in which atoms molecules prepared one (or more) coherent laser(s) probed another set lasers. However, generating using maximally oscillation macromolecules having an enormous number degrees...
We propose a scheme for subwavelength localization of an atom conditioned upon the absorption weak probe field at particular frequency. Manipulating atom-field interaction on certain transition by applying drive fields nearby coupled transitions leads to interesting effects in spectrum field. exploit this fact and employ four-level system with three driving field, where one is standing-wave cavity. show that position along standing wave determined when probe-field measured. find frequency...
Previous studies have shown that the possible utility of two-photon laser as a squeezed-state generator is negated by spontaneous-emission fluctuations. We here show correlated--spontaneous-emission can produce light which both squeezed and free from
It has long been assumed in physics that for information to travel between two parties empty space, "Alice" and "Bob," physical particles have them. Here, using the "chained" quantum Zeno effect, we show how, ideal asymptotic limit, can be transferred Alice Bob without any traveling
We investigate the time evolution of entanglement various entangled states a two-qubit system exposed to either thermal or squeezed reservoirs. show that, except for vacuum reservoir, sudden-death always exists in and present explicit expression states. find that results from portion double excitation component initial state. In this sense, maximally do not have is more robust against quantum fluctuations reservoir.
A theory of the quantum-beat laser is developed using a general Fokker-Planck approach. An explicit expression for diffusion coefficient relative phase angle two modes derived. It shown that can vanish under certain conditions.
Interaction of the internal states an atom with spatially dependent standing-wave cavity field can impart position information passing through it leading to subwavelength localization. We recently demonstrated a new regime localization [Sahrai {\it et al.}, Phys. Rev. A {\bf 72}, 013820 (2005)], namely sub-half-wavelength phase control electromagnetically induced transparency. This corresponds extreme atoms within chosen half-wavelength region field. Here we present further investigation...
Entanglement of a system changes due to interactions with the environment. A typical type interaction is amplitude damping. If we add detector monitor environment and only select no-damping outcome, this damping modified into weak measurement. Here show that entanglement change two-qubit state or measurement can be probabilistically reversed. For amplitude-damping case, partially recovers under most conditions. weak-measurement recovery initial entangled exact. The reversal procedure...
We present a proposal to manipulate the Goos-H\"anchen shift of light beam via coherent control field, which is injected into cavity configuration containing two-level atomic medium. It found that lateral shifts reflected and transmitted probe beams can be easily controlled by adjusting intensity detuning field. Using this scheme, at fixed incident angle enhanced (positive or negative) under suitable conditions on without changing structure cavity.
We show that the counterrotating, neglected in previous studies of quantum Zeno effect (QZE) atomic decay, can have a large impact on short-time evolution. calculate electron self-energy, Lamb shift, and QZE without making rotating-wave approximation (RWA) that, for hydrogen free space, time is longer by 2 orders magnitude than obtained from RWA. also there no anti-Zeno as counterrotating terms rotating represent opposite processes higher frequency region. Consequently, experimental...
We theoretically investigate the performance of multiphoton catalysis applied on two-mode squeezed state by examining entropy entanglement, logarithmic negativity, Eistein-Podolsky-Rosen (EPR), and Hillery-Zubairy (HZ) correlations, fidelity teleportation. It is found that entanglement increases with number operations if squeezing parameter low initially. Our comparisons show HZ correlation presents a better than EPR for detecting improvement definitely results in rather negativity; region...
We study the dynamics of a single-photon pulse traveling through linear atomic chain coupled to one-dimensional (1D) single mode photonic waveguide. derive time-dependent dynamical theory for this collective many-body system which allows us real time evolution photon transport and excitations. Our analytical result is consistent with previous numerical calculations when there only one atom. For an chain, interaction between atoms mediated by waveguide can significantly change system. The...
The waveguide quantum electrodynamics (QED) system may have important applications in device and information technology. In this article we review the methods being proposed to calculate photon transport a one-dimensional (1D) coupled emitters. We first introduce Bethe ansatz approach input–output formalism stationary results of single transport. Then present dynamical time-dependent theory real-time evolution QED system. longtime limit, both calculation give same results. Finally, also...
Continuous-variable quantum key distribution (CV-QKD) provides an effective way to obtain the high secret rate, but is limited by practical techniques. To overcome this limitation, we investigate performance of CV-QKD protocols when non-Gaussian operations are applied both sides channels, including photon subtraction and addition, catalysis. A comparison also made between Gaussian modulation modulation. We show that optimal transmission distance cannot be improved at sender's side, it can...
We propose a simple scheme of atom localization based on resonance fluorescence from standing-wave field. The Rabi frequency is position dependent and therefore the spontaneously emitted photon carries information atomic center-of-mass motion. This leads to even during flight through
We consider the teleportation of entangled two-particle and multiparticle states present a scheme for that may be suitable both atomic or field inside high-Q cavities.
Spontaneous emission in photonic crystals with anisotropic three-dimensional dispersion relation is studied. If the upper level below a characteristic frequency omega(1), or above omega(2), between omega(1) and radiation localized field band gap, propagating frquency band, diffusion field, respectively. An analytical expression for Lamb shift obtained. The current case small compared to that an ordinary vacuum one- two-dimensional due lower density of states.
We demonstrate tunable control of the group velocity a weak probe pulse from subluminal to superluminal. The model is an extended $\ensuremath{\Lambda}$-type system with two extra fields and energy level. Phase variation one imparts tunability in along other interesting spectral behavior absorption spectrum.