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

Physical Review B

Spin-system radio-frequency superradiation: A phenomenological study and comparison with numeric simulations

C. L. Davis, Victor K. Henner, Alexander Tchernatinsky, I. V. Kaganov

Published Aug 2, 2005• 14 citations
Publisher

Abstract

We discuss the coherent behavior of a polarized, nuclear or electron, spin system for which the magnetic dipole radiation emitted in the radio-frequency region, has approximately quadratic dependence on the number of spins. An effective method of describing these phenomena is provided by computer simulation of a microscopic model of the spin system. Important aspects of this numeric simulation are described, together with a comparison with the theoretical predictions. The behavior of the transverse component of the magnetic moment, ${M}^{+}(t)$, in super-radiant conditions is studied. In addition, the role of dipole-dipole interactions in super-radiation phenomena is investigated in detail. It is shown that some important features of super-radiation cannot be described with the Bloch equations.

DOI
10.1103/physrevb.72.054406

Related papers

Computer simulation of spin superradiance

Tatyana Belozerova, Victor K. Henner, Vyacheslav I. Yukalov

Coherent effects in polarized systems of nuclear or electron spins using a microscopic model are studied, but not the Bloch equations. It is shown that the spin system in a resonance circuit can emit a coherent superradiant pulse when the system is initially in an essentially unstable state, at a time much shorter than the spin dephasing time T2 when the coupling of the system with the circuit is sufficiently strong, and at the time longer than T2 when this coupling is weak. The important role if dipole spin-spin interactions is elucidated.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 3, 1994•0 citations

Non-Dicke superradiance in spin systems

Vyacheslav I. Yukalov

Superradiance in spin systems is studied theoretically on the basis of a microscopic model corresponding to nuclear magnets with dipole spin interactions. The onset of pure superradiance is shown to be caused by nonsecular spin interactions. While the effective interaction of spins through the common radiation field, as well as the resonator thermal-noise field, are not able to initiate coherent self-organization resulting in superradiance.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 26, 1997•0 citations

Super-radiance of multi-spin systems

M. G. Benedict, A. M. Ermolaev, Viktor A. Malyshev +2 more

This chapter is devoted mainly to the description and theoretical interpretation of super-radiance experiments in a multi-proton spin system. It considers the simplest case of multi-spin super-radiance in a cavity. The spin magnetic moment in a static magnetic field is a perfect realization of the 'two-level' atomic model. In fact, this physical system was the origin of this model, and was extended to a wide class of resonant phenomena, including super-radiance. A refined description of super-radiance of magnetic spins in solids will probably have to take into account the dependence of the relaxation rate on the magnitude of the magnetization, using as a basis the concept of spin temperature. The chapter shows the limitations of the method of Bloch equations for describing NMR effects in solids, as mentioned earlier in the literature. It attempts to observe super-radiance in the radiofrequency domain was reported by P. Bosiger and their group, using a nuclear subsystem of Al atoms in ruby crystals.

CRC Press eBooks•Mar 29, 2018•0 citations

Nuclear superradiance of the spin system

Dmitry S. Bulyanitsa, Andrey V. Druzhin, Evgeni D. Trifonov

ABSTRACT It is shown that the magnetic field local inhomogeneous, caused by the stochastic spin distribution over the volume,effects significantly on the nuclear superradiation process. Keywords: Dicke superradiance, nuclear spin system 1. INTRODUCTION The possibility of the Dicke superradiance' in the nuclear spin system, placed in the magnetic field, was explained byBlombergen and Paund in 1954.2 Experimental researches of this effect related to more later time.3'4 The theoretical explanation of this experiment, based on the solution of the Maxwell - Bloch equations system was proposed (seealso7) in works.5'6 Further development of the nuclear spin superradiance theory is contained in works.8'4 A semi-classical approach,5'6 reproducing main features of the observed effect, contained a number of artificial assumptions. In particular, observation of the single pulses regime with high values of the initial spin polarizations couldn't beexplained with taking in account of Larmor frequency scanning, that took place in the experiment. To obtain thecorrespondence with the experimental data we had to artificially select the transverse relaxation time value.In the present paper we throw out these assumptions and show that the role of additional relaxation mechanismcan play line width, caused by the local magnetic field. Here we are not pretend to give the exact description of thementioned experiment,4 but only point to the sufficiently features of the phenomenon considered.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jan 14, 2000•0 citations

Effect of spin-spin interaction on the super-radiant phase transition for the Dicke Hamiltonian

C. M. Bowden, Chi C. Sung

The thermodynamic equilibrium properties of the Dicke Hamiltonian for a collection of spin- 1 / 2 particles interacting via magnetic dipole interaction with a single mode of the radiation field and with each other by spin-spin interaction are analysed and the conditions for the existence of a super-radiant phase transition are derived. It is shown, using the approximate long-range spin-spin interaction (MI), in the Dicke Hamiltonian, that the conditions for the existence of the super-radiant phase transition are invariant with respect to isotropic MI whether or not the A 2 term is included.

Journal of Physics A Mathematical and General•Jan 1, 1978•7 citations

Superradiation in magnetic resonance

C. L. Davis, I. V. Kaganov, Victor K. Henner

The phenomenon of superradiation due to a resonant circuit and the backward influence of the radiation field in a standard magnetic resonance experiment is investigated. It is shown that although the effect of this phenomenon in the radio-frequency region is small, it leads to a change in the shape of the absorption line, which may be possible to observe in an appropriately designed experiment. The predicted shape of the wings of the absorption curve is unusual in magnetic resonance. This analysis, using a traditional magnetic resonance approach, compares favorably with the results of a numerical simulation of superradiation from a system of spins.

Physical review. B, Condensed matter•Nov 1, 2000•10 citations
We discuss the coherent behavior of a polarized, nuclear or electron, spin system for which the magnetic dipole radiation emitted in the radio-frequency region, has approximately quadratic dependence on the number of spins. An effective method of describing these phenomena is provided by computer simulation of a microscopic model of the spin system. Important aspects of this numeric simulation are described, together with a comparison with the theoretical predictions. The behavior of the transverse component of the magnetic moment, M+(t){M}^{+}(t)M+(t), in super-radiant conditions is studied. In addition, the role of dipole-dipole interactions in super-radiation phenomena is investigated in detail. It is shown that some important features of super-radiation cannot be described with the Bloch equations.
Coherent effects in polarized systems of nuclear or electron spins using a microscopic model are studied, but not the Bloch equations. It is shown that the spin system in a resonance circuit can emit a coherent superradiant pulse when the system is initially in an essentially unstable state, at a time much shorter than the spin dephasing time T2 when the coupling of the system with the circuit is sufficiently strong, and at the time longer than T2 when this coupling is weak. The important role if dipole spin-spin interactions is elucidated.
This chapter is devoted mainly to the description and theoretical interpretation of super-radiance experiments in a multi-proton spin system. It considers the simplest case of multi-spin super-radiance in a cavity. The spin magnetic moment in a static magnetic field is a perfect realization of the 'two-level' atomic model. In fact, this physical system was the origin of this model, and was extended to a wide class of resonant phenomena, including super-radiance. A refined description of super-radiance of magnetic spins in solids will probably have to take into account the dependence of the relaxation rate on the magnitude of the magnetization, using as a basis the concept of spin temperature. The chapter shows the limitations of the method of Bloch equations for describing NMR effects in solids, as mentioned earlier in the literature. It attempts to observe super-radiance in the radiofrequency domain was reported by P. Bosiger and their group, using a nuclear subsystem of Al atoms in ruby crystals.
ABSTRACT It is shown that the magnetic field local inhomogeneous, caused by the stochastic spin distribution over the volume,effects significantly on the nuclear superradiation process. Keywords: Dicke superradiance, nuclear spin system 1. INTRODUCTION The possibility of the Dicke superradiance' in the nuclear spin system, placed in the magnetic field, was explained byBlombergen and Paund in 1954.2 Experimental researches of this effect related to more later time.3'4 The theoretical explanation of this experiment, based on the solution of the Maxwell - Bloch equations system was proposed (seealso7) in works.5'6 Further development of the nuclear spin superradiance theory is contained in works.8'4 A semi-classical approach,5'6 reproducing main features of the observed effect, contained a number of artificial assumptions. In particular, observation of the single pulses regime with high values of the initial spin polarizations couldn't beexplained with taking in account of Larmor frequency scanning, that took place in the experiment. To obtain thecorrespondence with the experimental data we had to artificially select the transverse relaxation time value.In the present paper we throw out these assumptions and show that the role of additional relaxation mechanismcan play line width, caused by the local magnetic field. Here we are not pretend to give the exact description of thementioned experiment,4 but only point to the sufficiently features of the phenomenon considered.
The thermodynamic equilibrium properties of the Dicke Hamiltonian for a collection of spin- 1 / 2 particles interacting via magnetic dipole interaction with a single mode of the radiation field and with each other by spin-spin interaction are analysed and the conditions for the existence of a super-radiant phase transition are derived. It is shown, using the approximate long-range spin-spin interaction (MI), in the Dicke Hamiltonian, that the conditions for the existence of the super-radiant phase transition are invariant with respect to isotropic MI whether or not the A 2 term is included.
The phenomenon of superradiation due to a resonant circuit and the backward influence of the radiation field in a standard magnetic resonance experiment is investigated. It is shown that although the effect of this phenomenon in the radio-frequency region is small, it leads to a change in the shape of the absorption line, which may be possible to observe in an appropriately designed experiment. The predicted shape of the wings of the absorption curve is unusual in magnetic resonance. This analysis, using a traditional magnetic resonance approach, compares favorably with the results of a numerical simulation of superradiation from a system of spins.