Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Laser Physics

Efficient two-dimensional Fraunhofer diffraction pattern via electron spin coherence

H Meddour, Sh Askar, S Dehraj, F. Al-dolaimy, Barno Sayfutdinovna Abdullaeva, Ali Hashiem Alsaalamy, Mohammed N. Fenjan, Ahmed Hussien Alawadi, S H Kareem, Daha Thabit

Published Oct 6, 2023• 1 citation
Publisher

Abstract

Abstract In this letter, we have discussed the two-dimensional diffraction pattern via electron spin coherence in a GaAs quantum dot. Impulsive stimulated Raman excitation utilizing coherent optical fields is employed for the purpose of regulating the electron spin coherence within a charged ensemble of GaAs quantum dots, by means of an intermediate charged exciton (trion) state. We show that for the coupling two-dimensional standing wave (SW) field in the x and y directions, the two-dimensional Fraunhofer pattern can be formed for a weak probe light. By using the experimental parameters and controlling the Rabi frequency of the SW field and relative phase between applied lights, the symmetry and asymmetry diffraction pattern are obtained for the weak probe light due to the four-wave mixing mechanism. Our proposed model may have potential applications in high-capacity optical communications and quantum information technologies.

DOI
10.1088/1555-6611/acfd9a

Related papers

Ultrafast optical control of electron spin coherence in charged GaAs quantum dots

M. V. Gurudev Dutt, Jun Cheng, Yanwen Wu +7 more

Impulsive stimulated Raman excitation with coherent optical fields is used for controlling the electron spin coherence in a charged $\mathrm{GaAs}$ quantum dot ensemble through an intermediate charged exciton (trion) state. The interference between two stimulated Raman two-photon quantum mechanical pathways leading to the spin coherence allows us to control the electron spin coherence on the time scale of the Larmor precession frequency. We also demonstrate, both theoretically and experimentally, that ultrafast manipulation of the spin coherence is possible on the time scale of the optical laser frequency, and analyze the limitations due to the trion and spin decoherence times.

Physical Review B•Sep 13, 2006•43 citations

Orbital angular momentum induced asymmetric diffraction grating in quantum dot molecule

Weiyong Wang, Fanfan Niu, Qiao Na

Abstract In this paper, we study the Fraunhofer diffraction pattern in a four-level quantum dot nanostructure. The quantum dot interacts with two weak probe and signal laser fields and two strong coupling lights where one of them is a two-dimensional standing wave field. We study the Fraunhofer diffraction pattern of the transmitted probe light when the coherent driving light becomes plan wave or Laguerre Gaussian (LG) vortex light. We found that by controlling the relative phase of the applied lights and orbital angular momentum (OAM) of LG light, the Fraunhofer diffraction pattern can be controlled and the probe energy transfer from zero order to the higher orders, respectively. Moreover, we realized that by controlling the OAM number of the vortex light the asymmetric diffraction pattern is possible.

Laser Physics Letters•Apr 12, 2023•1 citation

Electromagnetically induced grating in azimuthal dependent three-level quantum dot system

A. P. Aslla-Quispe, Ever William Camacho-Orbegoso, Marilú Farfán Latorre +7 more

Abstract The Fraunhofer diffraction pattern in a three-level quantum dot nanostructure is examined. A probe light, a two-dimensional standing wave field, and a weak signal light are the three optical laser fields that the graphene quantum dot interacts with them. The Fraunhofer diffraction pattern of the probe transmitted light has been addressed under two different coupling situations, including when the weak signal light into an optical vortex beam and a plane wave. The Fraunhofer diffraction pattern becomes symmetric for plane wave coupling light, and the diffracted light can be adjusted by the relative phase between applied lights. However, using the orbital angular momentum of light, it is possible to obtain an asymmetric diffraction pattern for optical light. It has been discovered that in both instances, phase modulation of the probe light’s transmission function allows the probe energy to move from zero order to higher orders.

Laser Physics•May 19, 2023•0 citations

Microwave assisted Fraunhofer diffraction pattern in a four-level light–matter coupling scheme

Malika Amari, Carlos Rodriguez‐Benites, Alaa A. Omran +4 more

Abstract The experimental realization of two-dimensional (2D) electromagnetically induced grating is explored by monitoring the Fraunhofer diffraction pattern in a microwave-driven four-level Y-type atomic medium under the action of two orthogonal standing-wave (SW) fields. Due to the position-dependent atom–field interaction, the information about the high diffraction order of the probe light can be obtained via the Fraunhofer diffraction pattern of the probe light. It is found that the diffraction behavior is significantly improved due to the joint quantum interference induced by the SW and microwave-driven cycling fields. Most importantly, the amplitude and phase diagram of the transmission function of the probe light can be modulated at a particular position and the probe energy may transfer to the high orders of the diffraction by properly adjusting the system parameters. The proposed scheme may provide a promising way to achieve highly sensitive diffraction patterns with applications in quantum information processing.

Laser Physics•Apr 11, 2024•0 citations

Controlling 2D-fraunhofer diffraction in nonlinear optomechanical systems with atomic ensembles

Ning Fu, Pengju Kuang, Lei Ni +2 more

Abstract In this letter, we propose a novel nonlinear optomechanical system for generating a two-dimensional (2D) optical grating. The system comprises a Fabry–Pérot cavity with a fixed mirror, movable end mirror, degenerate optical parametric amplifier (OPA), and ensemble of identical two-level atoms. By applying a 2D asymmetric standing wave as the driving field, the probe light can be diffracted in the x - and y -directions with different intensities, leading to an asymmetric optomechanically induced grating. The amplitude and phase modulations of the output probe light and the resulting Fraunhofer diffraction patterns were investigated. The results show that the atomic ensemble plays a crucial role in controlling the efficiency and asymmetry of 2D gratings. We demonstrate that by tuning the nonlinear gain of the OPA and higher-order excitations of the atoms, the transparency of the medium can be enhanced, leading to greater transmission of probe energy and transfer to higher diffraction orders. The proposed system offers a novel approach for generating asymmetric 2D optical gratings in optomechanical devices with potential applications in quantum information science.

Laser Physics Letters•Jan 1, 2026•2 citations

Coherent optical manipulation of electron spin in charged semiconductor quantum dots.

Meenakshi Dutt

In this work, we study the resonant nonlinear optical response obtained when optical fields are used to excite charged semiconductor quantum dots (QDs). The basic physics of charged excitons (trions) created by optical excitation of charged QDs is of interest from the point of view of optically driven spin based quantum computing (QC). Stimulated Raman excitation, resonantly enhanced by the optical dipole coupling to the trion state, was used to optically generate electron spin coherence in the ground state of charged QDs. The evolution of the spin coherence was monitored through quantum beats in the phase-sensitively detected four wave mixing signal. The decay of the beats is a measure of the spin coherence time, which was found to be at least an order of magnitude greater than either the trion dipole coherence, or the Raman coherence time between excitons in a single neutral QD. A fascinating outcome of the experiment was the first observation of a contribution to the spin coherence induced by the vacuum field, which is also responsible for spontaneous emission from the trion state, known as spontaneously generated coherence (SGC). QC demands that coherent optical manipulations should be performed within the spin coherence time. We performed coherent optical control experiments, with a pair of phase-locked pump pulses, that showed the quantum nature of the coherence through interference of different quantum mechanical pathways. We showed both in experiment and theory that we can manipulate the spin coherence on the time scale of the Larmor frequency, as well as on an ultrafast femtosecond time scale, corresponding to the optical frequency of the trion state. Finally, resonant optical excitation of both the bright and nominally forbidden transitions from a single electron spin in a QD to the trion state were demonstrated. This allows for direct optical access to all the transitions required for optically driven QC with QD electron spins. We used frequency-domain nonlinear spectroscopy measurements on single QD trions to obtain the trion dipole decoherence and decay rates. Further, we demonstrated that the single electron spin coherence could be generated and detected optically, and found that the spin coherence time was significantly greater than in ensemble measurements at the same magnetic field.

•Jan 1, 2004•0 citations
Abstract In this letter, we have discussed the two-dimensional diffraction pattern via electron spin coherence in a GaAs quantum dot. Impulsive stimulated Raman excitation utilizing coherent optical fields is employed for the purpose of regulating the electron spin coherence within a charged ensemble of GaAs quantum dots, by means of an intermediate charged exciton (trion) state. We show that for the coupling two-dimensional standing wave (SW) field in the x and y directions, the two-dimensional Fraunhofer pattern can be formed for a weak probe light. By using the experimental parameters and controlling the Rabi frequency of the SW field and relative phase between applied lights, the symmetry and asymmetry diffraction pattern are obtained for the weak probe light due to the four-wave mixing mechanism. Our proposed model may have potential applications in high-capacity optical communications and quantum information technologies.
Impulsive stimulated Raman excitation with coherent optical fields is used for controlling the electron spin coherence in a charged GaAs\mathrm{GaAs}GaAs quantum dot ensemble through an intermediate charged exciton (trion) state. The interference between two stimulated Raman two-photon quantum mechanical pathways leading to the spin coherence allows us to control the electron spin coherence on the time scale of the Larmor precession frequency. We also demonstrate, both theoretically and experimentally, that ultrafast manipulation of the spin coherence is possible on the time scale of the optical laser frequency, and analyze the limitations due to the trion and spin decoherence times.
Abstract In this paper, we study the Fraunhofer diffraction pattern in a four-level quantum dot nanostructure. The quantum dot interacts with two weak probe and signal laser fields and two strong coupling lights where one of them is a two-dimensional standing wave field. We study the Fraunhofer diffraction pattern of the transmitted probe light when the coherent driving light becomes plan wave or Laguerre Gaussian (LG) vortex light. We found that by controlling the relative phase of the applied lights and orbital angular momentum (OAM) of LG light, the Fraunhofer diffraction pattern can be controlled and the probe energy transfer from zero order to the higher orders, respectively. Moreover, we realized that by controlling the OAM number of the vortex light the asymmetric diffraction pattern is possible.
Abstract The Fraunhofer diffraction pattern in a three-level quantum dot nanostructure is examined. A probe light, a two-dimensional standing wave field, and a weak signal light are the three optical laser fields that the graphene quantum dot interacts with them. The Fraunhofer diffraction pattern of the probe transmitted light has been addressed under two different coupling situations, including when the weak signal light into an optical vortex beam and a plane wave. The Fraunhofer diffraction pattern becomes symmetric for plane wave coupling light, and the diffracted light can be adjusted by the relative phase between applied lights. However, using the orbital angular momentum of light, it is possible to obtain an asymmetric diffraction pattern for optical light. It has been discovered that in both instances, phase modulation of the probe light’s transmission function allows the probe energy to move from zero order to higher orders.
Abstract The experimental realization of two-dimensional (2D) electromagnetically induced grating is explored by monitoring the Fraunhofer diffraction pattern in a microwave-driven four-level Y-type atomic medium under the action of two orthogonal standing-wave (SW) fields. Due to the position-dependent atom–field interaction, the information about the high diffraction order of the probe light can be obtained via the Fraunhofer diffraction pattern of the probe light. It is found that the diffraction behavior is significantly improved due to the joint quantum interference induced by the SW and microwave-driven cycling fields. Most importantly, the amplitude and phase diagram of the transmission function of the probe light can be modulated at a particular position and the probe energy may transfer to the high orders of the diffraction by properly adjusting the system parameters. The proposed scheme may provide a promising way to achieve highly sensitive diffraction patterns with applications in quantum information processing.
Abstract In this letter, we propose a novel nonlinear optomechanical system for generating a two-dimensional (2D) optical grating. The system comprises a Fabry–Pérot cavity with a fixed mirror, movable end mirror, degenerate optical parametric amplifier (OPA), and ensemble of identical two-level atoms. By applying a 2D asymmetric standing wave as the driving field, the probe light can be diffracted in the x - and y -directions with different intensities, leading to an asymmetric optomechanically induced grating. The amplitude and phase modulations of the output probe light and the resulting Fraunhofer diffraction patterns were investigated. The results show that the atomic ensemble plays a crucial role in controlling the efficiency and asymmetry of 2D gratings. We demonstrate that by tuning the nonlinear gain of the OPA and higher-order excitations of the atoms, the transparency of the medium can be enhanced, leading to greater transmission of probe energy and transfer to higher diffraction orders. The proposed system offers a novel approach for generating asymmetric 2D optical gratings in optomechanical devices with potential applications in quantum information science.
In this work, we study the resonant nonlinear optical response obtained when optical fields are used to excite charged semiconductor quantum dots (QDs). The basic physics of charged excitons (trions) created by optical excitation of charged QDs is of interest from the point of view of optically driven spin based quantum computing (QC). Stimulated Raman excitation, resonantly enhanced by the optical dipole coupling to the trion state, was used to optically generate electron spin coherence in the ground state of charged QDs. The evolution of the spin coherence was monitored through quantum beats in the phase-sensitively detected four wave mixing signal. The decay of the beats is a measure of the spin coherence time, which was found to be at least an order of magnitude greater than either the trion dipole coherence, or the Raman coherence time between excitons in a single neutral QD. A fascinating outcome of the experiment was the first observation of a contribution to the spin coherence induced by the vacuum field, which is also responsible for spontaneous emission from the trion state, known as spontaneously generated coherence (SGC). QC demands that coherent optical manipulations should be performed within the spin coherence time. We performed coherent optical control experiments, with a pair of phase-locked pump pulses, that showed the quantum nature of the coherence through interference of different quantum mechanical pathways. We showed both in experiment and theory that we can manipulate the spin coherence on the time scale of the Larmor frequency, as well as on an ultrafast femtosecond time scale, corresponding to the optical frequency of the trion state. Finally, resonant optical excitation of both the bright and nominally forbidden transitions from a single electron spin in a QD to the trion state were demonstrated. This allows for direct optical access to all the transitions required for optically driven QC with QD electron spins. We used frequency-domain nonlinear spectroscopy measurements on single QD trions to obtain the trion dipole decoherence and decay rates. Further, we demonstrated that the single electron spin coherence could be generated and detected optically, and found that the spin coherence time was significantly greater than in ensemble measurements at the same magnetic field.