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

arXiv:1708.07793

Quantum Dynamics of a Two-level System Near a Gold Nanoparticle

Somayeh M. A. Mirzaee, Chitra Rangan

Published Aug 25, 2017• 0 citations
arXivHTMLPDF

Abstract

The ability to prepare desired states without allowing time for the atomic system to spontaneously decay to the ground state is limited by the fact that Hamiltonian controls cannot affect the purity of the state in question. In this paper, we discuss how a continuous off-resonant electromagnetic wave can be used to prepare a desired final quantum state. With the aid of plasmonic surface-enhancement, by placing a two-level atomic system near a gold nanoparticle, preparation is accomplished in a reduced period of time and with lower electric field intensity while the system purity is improved when compared to an isolated system.

DOI
10.48550/arxiv.1708.07793

Related papers

QUANTUM DYNAMICS OF A TWO-LEVEL ATOM NEAR GOLD NANOSTRUCTURES

Somayeh M. A. Mirzaee

When an atomic/molecular system controlled by an external field (to imprint information on it, such as preparing a qubit), is brought near a plasmonic nanostructure, the control problem changes. On one hand, the field experienced by the atom is modified due to the plasmon effects of the nanostructure. On the other hand, due to atom-nanostructure interactions the quantum state spontaneous emission is increased. Purification of states is fundamental to the implementation of quantum technologies. My approach for state purification is based on the interplay of control fields and spontaneous emission from a two-level quantum system in presence of a gold nanoparticle (GNP). For a specific location of the system around the GNP, I can find a control field that increases the purity of the system more than without the GNP. Unlike previous efforts of state purification that involve cooling to the ground state, here the excited state population remains significant.

•Jan 1, 2012•1 citation

Prolonging entanglement dynamics near periodic plasmonic nanostructures

Nikos Iliopoulos, Andreas Terzis, Vassilios Yannopapas +1 more

We study the dynamics of two initially entangled qubits, where each one interacts locally and independently of the other, with a plasmonic nanostructure. By considering two different cases for the qubits, two identical two-level systems and two identical V-type quantum systems, where one two-level transition plays the role of the qubit while the third level acts as an ``umbrella level'', we study the corresponding entanglement dynamics for several pure and mixed initial states. As the plasmonic nanostructure we take a two-dimensional lattice of metal-coated dielectric nanoparticles. The presence of this nanostructure leads to highly suppressed spontaneous emission rates of the individual quantum systems, as well as to highly anisotropic spontaneous decay rates for orthogonal dipole matrix elements due to the anisotropic Purcell effect, leading to quantum interference in spontaneous emission. Both of the effects can be used for significantly prolonging the time evolution of entanglement for several system parameters.

Physical review. B./Physical review. B•Aug 4, 2017•27 citations

Numerical modelling of emission of a two-level atom near a metal nanoparticle with account for tunnelling of an electron from an atom into a particle

S. V. Fedorovich, Игорь Евгеньевич Проценко

We report the results of numerical modelling of emission of a two-level atom near a metal nanoparticle under resonant interaction of light with plasmon modes of the particle. Calculations have been performed for different polarisations of light by a dipole approximation method and a complex multipole method. Depending on the distance between a particle and an atom, the contribution of the nonradiative process of electron tunnelling from a two-level atom into a particle, which is calculated using the quasi-classical approximation, has been taken into account and assessed. We have studied spherical gold and silver particles of different diameters . The rates of electron tunnelling and of spontaneous decay of the excited atomic state are found. The results can be used to develop nanoscale plasmonic emitters, lasers and photodetectors.

Quantum Electronics•Jan 31, 2016•0 citations

Modification of two-level-atom resonance fluorescence near a plasmonic nanostructure

Yu. V. Vladimirova, В. В. Климов, Vladimir Pastukhov +1 more

Modification of the resonance fluorescence spectrum of a two-level atom driven by a monochromatic field in the close proximity of a plasmonic nanostructure (metal sphere) is studied in detail. It is shown that one can control this spectrum by varying several key parameters: (i) the radius of the nanosphere, (ii) polarization of the incident radiation, and (iii) the atom's location around the nanosphere (its radial coordinate and polar angle in the spherical coordinate system). These parameters affect the local field enhancement and the modification of the radiative decay rate of the atom interacting with the nanosphere, which leads to modification of the resonance fluorescence spectrum of the atom (e.g., frequency shift of the satellite lines in the Mollow-type triplet, widths of the lines, and the spectrum intensity) by contrast with that in free space. The permittivity of the metal the nanosphere is made of is also an additional parameter, which defines the nonradiative decay. The latter in combination with other parameters allows continuous control of the transition from resonance fluorescence enhancement to its quenching.

Physical Review A•May 7, 2012•51 citations

Resonance fluorescence of a two-level quantum emitter near a plasmonic nanoparticle: role of the near-field polarization

Yu. V. Vladimirova, Eugeny D. Chubchev, Victor N. Zadkov

Abstract It is demonstrated that the interaction of a two-level quantum emitter (atom, molecule, etc) with a plasmonic nanoparticle (prolate nanospheroid) in an external laser field features either an essential increase (up to a few orders of magnitude) or reduction (up to a few times) of the total decay rate of the emitter in specific areas around the nanoparticle in contrast to its decay rate in a vacuum. It is also shown that the resonance fluorescence spectrum of the emitter in close proximity to a plasmonic nanoparticle is very sensitive to both the location of the emitter around the nanoparticle and to polarization of the near-field, which depends in turn on the polarization of the incident laser field. This can be used in engineering potential quantum optics experiments with quantum emitters in the near-field, as well as for 3D nanoscopy of the near-field by registering the resonance fluorescence spectra of quantum emitters scattered in the vicinity of a plasmonic nanoparticle.

Laser Physics•Jan 6, 2017•3 citations

Tunable Switching between Slow and Fast Light in the Double Metal Nanoparticles (MNPs)-Quantum Dot (QD) Plasmonic Hybrid Systems

Maram Al Maqtouf, Mariam M. Tohari

Plasmonic nanocomposites have the ability to enhance light-matter interaction due to the plasmonic effects leading to promising potential applications. In this paper, we theoretically study the group index of the silver nanoparticle-gold nanoparticle-quantum dot plasmonic hybrid system in the optical region of the electromagnetic spectrum using the density matrix approach. The quantum dot is considered to be a three-level atomic system of a lambda configuration, interacting with strong control and weak probe fields. We find that the plasmonic hybrid system exhibits at near resonance a strong switching between slow and fast light, which can be controlled by the inclination angle of the gold nanoparticle and the size of the metals nanoparticles, in addition to the strength and detuning of the control field. Thus, the silver nanoparticle-gold nanoparticle-quantum dot could potentially be used in optoelectronic devices.

•Nov 20, 2023•1 citation
The ability to prepare desired states without allowing time for the atomic system to spontaneously decay to the ground state is limited by the fact that Hamiltonian controls cannot affect the purity of the state in question. In this paper, we discuss how a continuous off-resonant electromagnetic wave can be used to prepare a desired final quantum state. With the aid of plasmonic surface-enhancement, by placing a two-level atomic system near a gold nanoparticle, preparation is accomplished in a reduced period of time and with lower electric field intensity while the system purity is improved when compared to an isolated system.
When an atomic/molecular system controlled by an external field (to imprint information on it, such as preparing a qubit), is brought near a plasmonic nanostructure, the control problem changes. On one hand, the field experienced by the atom is modified due to the plasmon effects of the nanostructure. On the other hand, due to atom-nanostructure interactions the quantum state spontaneous emission is increased. Purification of states is fundamental to the implementation of quantum technologies. My approach for state purification is based on the interplay of control fields and spontaneous emission from a two-level quantum system in presence of a gold nanoparticle (GNP). For a specific location of the system around the GNP, I can find a control field that increases the purity of the system more than without the GNP. Unlike previous efforts of state purification that involve cooling to the ground state, here the excited state population remains significant.
We study the dynamics of two initially entangled qubits, where each one interacts locally and independently of the other, with a plasmonic nanostructure. By considering two different cases for the qubits, two identical two-level systems and two identical V-type quantum systems, where one two-level transition plays the role of the qubit while the third level acts as an ``umbrella level'', we study the corresponding entanglement dynamics for several pure and mixed initial states. As the plasmonic nanostructure we take a two-dimensional lattice of metal-coated dielectric nanoparticles. The presence of this nanostructure leads to highly suppressed spontaneous emission rates of the individual quantum systems, as well as to highly anisotropic spontaneous decay rates for orthogonal dipole matrix elements due to the anisotropic Purcell effect, leading to quantum interference in spontaneous emission. Both of the effects can be used for significantly prolonging the time evolution of entanglement for several system parameters.
We report the results of numerical modelling of emission of a two-level atom near a metal nanoparticle under resonant interaction of light with plasmon modes of the particle. Calculations have been performed for different polarisations of light by a dipole approximation method and a complex multipole method. Depending on the distance between a particle and an atom, the contribution of the nonradiative process of electron tunnelling from a two-level atom into a particle, which is calculated using the quasi-classical approximation, has been taken into account and assessed. We have studied spherical gold and silver particles of different diameters . The rates of electron tunnelling and of spontaneous decay of the excited atomic state are found. The results can be used to develop nanoscale plasmonic emitters, lasers and photodetectors.
Modification of the resonance fluorescence spectrum of a two-level atom driven by a monochromatic field in the close proximity of a plasmonic nanostructure (metal sphere) is studied in detail. It is shown that one can control this spectrum by varying several key parameters: (i) the radius of the nanosphere, (ii) polarization of the incident radiation, and (iii) the atom's location around the nanosphere (its radial coordinate and polar angle in the spherical coordinate system). These parameters affect the local field enhancement and the modification of the radiative decay rate of the atom interacting with the nanosphere, which leads to modification of the resonance fluorescence spectrum of the atom (e.g., frequency shift of the satellite lines in the Mollow-type triplet, widths of the lines, and the spectrum intensity) by contrast with that in free space. The permittivity of the metal the nanosphere is made of is also an additional parameter, which defines the nonradiative decay. The latter in combination with other parameters allows continuous control of the transition from resonance fluorescence enhancement to its quenching.
Abstract It is demonstrated that the interaction of a two-level quantum emitter (atom, molecule, etc) with a plasmonic nanoparticle (prolate nanospheroid) in an external laser field features either an essential increase (up to a few orders of magnitude) or reduction (up to a few times) of the total decay rate of the emitter in specific areas around the nanoparticle in contrast to its decay rate in a vacuum. It is also shown that the resonance fluorescence spectrum of the emitter in close proximity to a plasmonic nanoparticle is very sensitive to both the location of the emitter around the nanoparticle and to polarization of the near-field, which depends in turn on the polarization of the incident laser field. This can be used in engineering potential quantum optics experiments with quantum emitters in the near-field, as well as for 3D nanoscopy of the near-field by registering the resonance fluorescence spectra of quantum emitters scattered in the vicinity of a plasmonic nanoparticle.
Plasmonic nanocomposites have the ability to enhance light-matter interaction due to the plasmonic effects leading to promising potential applications. In this paper, we theoretically study the group index of the silver nanoparticle-gold nanoparticle-quantum dot plasmonic hybrid system in the optical region of the electromagnetic spectrum using the density matrix approach. The quantum dot is considered to be a three-level atomic system of a lambda configuration, interacting with strong control and weak probe fields. We find that the plasmonic hybrid system exhibits at near resonance a strong switching between slow and fast light, which can be controlled by the inclination angle of the gold nanoparticle and the size of the metals nanoparticles, in addition to the strength and detuning of the control field. Thus, the silver nanoparticle-gold nanoparticle-quantum dot could potentially be used in optoelectronic devices.