The history of the discovery, study, and explanation of the effect discovered fifty years ago by the German physicist Hanle and its development and generalization by the French school of physicists led by Kastler are described. The effect is observed optically in an increase in the degree of depolarization of the resonance fluorescence. It is studied in the range of magnetic fields in which the Zeeman splitting of the atomic magnetic sublevels does not exceed the level widths determined by thermal relaxation mechanisms and electromagnetic interaction. It is a direct optical manifestation of interference of degenerate atomic states and is intimately connected with the conservation law for the angular momentum of the photon-atom system. In the review, different applications of the effect to the measurement of mean lifetimes, linewidths, and Stark splitting constants of atoms in excited states are given. The resonance scattering of light by atoms in the ground state in a weak magnetic field is considered in detail—in particular, in the presence of radio-frequency magnetic fields oriented in different ways. The different possible types of parametric resonances in one or two radio-frequency fields for arbitrary orientation of the constant magnetic field are interpreted as the effect of crossing of the levels of an atom that is dressed by the radio-frequency field. Applications of the effect in the quantum magnetometry of ultraweak fields (down to 10-10 Oe) are examined.The history of the discovery, study, and explanation of the effect discovered fifty years ago by the German physicist Hanle and its development and generalization by the French school of physicists led by Kastler are described. The effect is observed optically in an increase in the degree of depolarization of the resonance fluorescence. It is studied in the range of magnetic fields in which the Zeeman splitting of the atomic magnetic sublevels does not exceed the level widths determined by thermal relaxation mechanisms and electromagnetic interaction. It is a direct optical manifestation of interference of degenerate atomic states and is intimately connected with the conservation law for the angular momentum of the photon-atom system. In the review, different applications of the effect to the measurement of mean lifetimes, linewidths, and Stark splitting constants of atoms in excited states are given. The resonance scattering of light by atoms in the ground state in a weak magnetic field is considered in detail—in particular, in the presence of radio-frequency magnetic fields oriented in different ways. The different possible types of parametric resonances in one or two radio-frequency fields for arbitrary orientation of the constant magnetic field are interpreted as the effect of crossing of the levels of an atom that is dressed by the radio-frequency field. Applications of the effect in the quantum magnetometry of ultraweak fields (down to 10-10 Oe) are examined.

Soviet Physics UspekhiApr 30, 197519 citations

Investigation of dynamic stark effect by means of coherence resonances of second kind

A. Faist

Physics Letters ASep 1, 19730 citations

Orientational Light Shift Experimental Estimate of 0-0 Resonance Frequency in Rubidium Vapor

Ермак Сергей Викторович, Roman Lozov, V. V. Semenov

The paper presents the measurements results of the orientational light shift of the radio-optical 0-0 resonance frequency in the rubidium vapor with isotopic pumping. The experiments were done on a laboratory quantum discriminator, the functional diagram of which contained a known element set for rubidium frequency standard on a gas cell. The discriminator was placed in the three identical pairs of Helmholtz coils, 50 cm in diameter, which created a working magnetic field (10 μT, 3 μT, and 1 μT) in the area of the gas cell. Helmholtz coils were connected to alternating voltage sources to create a rotating magnetic field relative to the normal to the direction of the pumping light. To weaken external magnetic noise and inhomogeneities of the laboratory magnetic field, the entire system was placed in a magnetic shield with a screening factor of ~ 103, which practically made it possible to exclude the effect of the residual field on the measurements accuracy. The main experimental results are formulated as follows: the orientational frequency shift of the 0-0 radio-optical resonance does not depend on the magnitude of the working magnetic field and is linearly related to the pumping light intensity; when the working magnetic field is oriented normal to the quantum discriminator optical axis, the tensor and scalar components of the light shift have equal (positive) signs, which at any temperature of the filter-cell leads to their impossible compensation; when the working magnetic field is oriented along the quantum discriminator optical axis, the tensor and scalar components of the light shift have opposite signs, which at the corresponding temperature of the filter-cell leads to their possible (partial) compensation.The paper presents the measurements results of the orientational light shift of the radio-optical 0-0 resonance frequency in the rubidium vapor with isotopic pumping. The experiments were done on a laboratory quantum discriminator, the functional diagram of which contained a known element set for rubidium frequency standard on a gas cell. The discriminator was placed in the three identical pairs of Helmholtz coils, 50 cm in diameter, which created a working magnetic field (10 μT, 3 μT, and 1 μT) in the area of the gas cell. Helmholtz coils were connected to alternating voltage sources to create a rotating magnetic field relative to the normal to the direction of the pumping light. To weaken external magnetic noise and inhomogeneities of the laboratory magnetic field, the entire system was placed in a magnetic shield with a screening factor of ~ 103, which practically made it possible to exclude the effect of the residual field on the measurements accuracy. The main experimental results are formulated as follows: the orientational frequency shift of the 0-0 radio-optical resonance does not depend on the magnitude of the working magnetic field and is linearly related to the pumping light intensity; when the working magnetic field is oriented normal to the quantum discriminator optical axis, the tensor and scalar components of the light shift have equal (positive) signs, which at any temperature of the filter-cell leads to their impossible compensation; when the working magnetic field is oriented along the quantum discriminator optical axis, the tensor and scalar components of the light shift have opposite signs, which at the corresponding temperature of the filter-cell leads to their possible (partial) compensation.

International Conference on Electrical Engineering and Photonics (EExPolytech)Oct 15, 20204 citations

Radio-frequency response of strongly interacting Fermi gases at finite temperatures

S. Y. Chang

The radio-frequency spectrum of the fermions in the unitary limit at finite temperatures is characterized by the sum-rule relations. We consider a simple picture where the atoms are removed by radio-frequency excitations from the strongly interacting states into a state of negligible interaction. We calculate the moments of the response function in the range of temperature $0.08{ϵ}_{F}<T<0.8{ϵ}_{F}$ using auxiliary field Monte Carlo technique in which continuum auxiliary fields with a density-dependent shift are used. We estimate the effects of superfluid pairing from the clock shift. We find a qualitative agreement with the pairing gap--pseudogap transition behavior. We also find within the quasiparticle picture that in order for the gap to come into quantitative agreement with the previously known value at $T=0$ , the effective mass has to be ${m}^{\ensuremath{\ast}}\ensuremath{\sim}1.43m$. Finally, we discuss implications for the adiabatic sweep of the resonant magnetic field.The radio-frequency spectrum of the fermions in the unitary limit at finite temperatures is characterized by the sum-rule relations. We consider a simple picture where the atoms are removed by radio-frequency excitations from the strongly interacting states into a state of negligible interaction. We calculate the moments of the response function in the range of temperature $0.08{ϵ}_{F}<T<0.8{ϵ}_{F}$ using auxiliary field Monte Carlo technique in which continuum auxiliary fields with a density-dependent shift are used. We estimate the effects of superfluid pairing from the clock shift. We find a qualitative agreement with the pairing gap--pseudogap transition behavior. We also find within the quasiparticle picture that in order for the gap to come into quantitative agreement with the previously known value at $T=0$, the effective mass has to be ${m}^{\ensuremath{\ast}}\ensuremath{\sim}1.43m$. Finally, we discuss implications for the adiabatic sweep of the resonant magnetic field.

arXiv:0905.2072Physical Review ASep 29, 20092 citations

Observation of the Resonant Stark Effect at Optical Frequencies

Felix Schuda, Carlos R. Stroud, Michael Hercher

Elsevier eBooksJan 1, 19830 citations

0.08{ϵ}_{F}<T<0.8{ϵ}_{F}

using auxiliary field Monte Carlo technique in which continuum auxiliary fields with a density-dependent shift are used. We estimate the effects of superfluid pairing from the clock shift. We find a qualitative agreement with the pairing gap--pseudogap transition behavior. We also find within the quasiparticle picture that in order for the gap to come into quantitative agreement with the previously known value at

T=0

, the effective mass has to be ${m}^{\ensuremath{\ast}}\ensuremath{\sim}1.43m$. Finally, we discuss implications for the adiabatic sweep of the resonant magnetic field.