We analyze the hanle effect on the closed f g equals 3 yields f e equals 4 d 2line transition of 85 rb, by both numerical solutions of the optical bloch equations and by experimental investigations on cell containing rubidium vapor. Additionally, a magnetic field may perturb and modify the line scattering polarization signals through the hanle effect. The hanle effect for the 3 2 s 1 2 3 2 p 1 2 transition of sodium. Timedependent behavior of linear polarization in unresolved. The hanle effect applied to magnetic field diagnostics. I am most pleased and, in a way, i feel honored to write the foreword for the book the hanle effect and levelcrossing spectroscopy, which covers such a very wide range of applications not only in the initial areas of atomic and molecular physics, but also in solid state physics, solar physics. Spin transport and the hanle effect in organic spintronics. The hanle e ect is a powerful diagnostic tool for the measurement of weak magnetic elds, deterministic or turbulent sten o 1978. The dnp induced by the hyperfine interaction has been probed via satellite peaks in nonlocal hanletype spin precession signals, indicating the recovery of electron spin. Vector integral equations for polarized transfer, are known to be useful for analytical work, numerical work and phenomenological analyses. This field induces a larmor precession in the excited atoms, and as they decay to the ground state the precession results in a time varying spatial distribution of the decay radiation. The effect is named after wilhelm hanle, who was the first to explain the effect, in terms of classical physics, in zeitschrift fur physik in 1924. Circularly polarized photoluminescence and hanle effect.
The hanle effect as a diagnostic of magnetic fields in. 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 hanle depolarization is separated from a number of other effects, including collisional depolarization and scattering. Hanle village, located in eastern indian ladakh, near the chinese border the indian astronomical observatory, adjacent to hanle village, location of the highest major astronomical telescopes in the world and colloquially known as hanle. However, when spin dephasing is very strong, hanle effect in a uniaxial magnetic field can be impossible to measure. Monographs that deal with atomic physics and polarized radiative transfer provide excellent treatments of the hanle effect. Polarization and the hanle effect polarizationis measuredin termsof the fourstokesvectorcomponents, i, q, u and v. For laser radiation with linear polarization orthogonal to the applied magnetic field, the hanle signal is. For laser radiation with linear polarization orthogonal to the applied magnetic field, the hanle signal is characterized by narrow bright resonances at low. The hanle effect has been extensively used for the determination of the magnetic field strength and direction in solar prominences.
Scattering polarization and hanle effect in stellar atmospheres with. This paper describes an experiment where the hanle effect in the ground state of an atomic transition is detected, not by a modification of the light absorbed or reemitted by the atoms, but by a modification of the atomic trajectories. Download fulltext pdf hanle effect for stellar dipoles and quadrupoles article pdf available in the astrophysical journal 7601 september 2012 with 35 reads. Download pdf 569 kb abstract this article presents an introduction to optical pumping, atomic polarization and the hanle effect in weakly magnetized stellar atmospheres. The field of organic spintronics has taken off since the discovery of large magnetoresistance in thick organic spin valves osvs. We compare theoretical modeling with experimental data from driftdominated silicon spintransport devices, illustrating the nontrivial consequences of employing oblique magnetic fields due to misalignment or intentional. Geometric dephasinglimited hanle effect in longdistance. This article presents an introduction to optical pumping, atomic polarization and the hanle effect in weakly magnetized stellar atmospheres.
A brief summary of the theory is presented and it is shown how the complete magnetic vector field can be recovered from the interpretation of the hanle effect in spectral lines polarized by resonance scattering. Contrary to the zeeman e ect, the hanle e ect leaves a signature on the polarization even for an isotropically distributed random eld with zero mean. The thickness of organic films 100 nm in these osvs should preclude direct. The hanle effect light from a secondary mercury source is shown onto a primary mercury vapor cell located in a slowly varying magnetic field. If energy levels are split in an external magnetic field, then. The hanle effect describes suppression of spin polarization due to precession in a magnetic field.
The existence of a cpl that is dependent on the helicity of the excitation laser, and the unexpectedly long spin lifetime. The hanle effect and its use for the measurements of very small magnetic. The stokes parameters amid an anisotropic radiation field and a magnetic field are derived as an analytical formula which enables us to conduct immediate analyses of observation data taken by spectropolarimetry. Evidence of spin precession and dephasing hanle effect induced by an external magnetic field is the only unequivocal proof of spinpolarized conduction electron transport in semiconductor devices. Hanle effect with angledependent partial redistribution. It is shown that optical pumping can be used to create alignment of states. Coherent population trapping with losses on the sodium d1. In conclusion, the hanle e ect is not a form of the faraday rotation.
The hanle effect and its use for the measurements of very small magnetic fields. Pdf tuning of the hanle effect from eit to eia using. The nonlinear hanle effect and its applications to laser physics. Tuning of the hanle effect from eit to eia using spatially.
The hanle effect is the modification by the local magnetic field of the linear polarization parameters of a spectral line. Q and u measure the intensity of linearly polarized light relative to two axes. Non perturbative calculation for a j 0 to j 1 transition. Apr 23, 2012 the spin hall effect is a relativistic spinorbit coupling phenomenon, which can be used to electrically generate or detect spin currents in nonmagnetic systems. We compare theoretical modeling with experimental data from driftdominated silicon spintransport devices, illustrating the nontrivial consequences of employing oblique magnetic fields due to misalignment or intentional, fixed inplane field. The influence of weak localization on hanle effect in a twodimensional system with spinsplit spectrum is considered. Pdf the hanle effect and level crossing spectroscopy in rb. Pdf the hanle effect is calculated for a random magnetic field characterized by. The hanle effect and the diagnostics of turbulent magnetic. The alternative tool is the hanle effect, a coherence phenomenon discovered 4 by wilhelm hanle in 1924.
We compare the different coherent population trapping schemes that can be established on the d1 line using the zeeman sublevels of a given ground hyperfine state. Calculations on the hanle effect with phase and amplitude. The hanle effect is measured to study spin relaxation in ch 3 nh 3 pbbr 3 film, yielding a spin lifetime of. If energy levels are split in an external magnetic eld, then in the range from weak to mediumstrength elds, the levels can indeed cross. Hanle effect is ubiquitous in the study of spinrelated phenomena and has been used to determine spin lifetime, precession and transport in semiconductors. As this is a relatively new area we will focus on the diagnostic methods and. May 14, 2018 we demonstrate a technique for continuous tuning of the hanle effect from electromagnetically induced transparency eit to electromagnetically induced absorption eia by changing the. As this is a relatively new area we will focus on the. Pdf the hanle effect applied to magnetic field diagnostics. The hanle effect for the 3 2s12 3 2p12 transition of sodium. Pdf we measure and simulate numerically the hanle effect and nonzero field level crossing signals in 85rb and 87rb atoms in a magnetic field at room. Analytical solution of the hanle effect in view of clasp and.
Sep 27, 2012 download fulltext pdf hanle effect for stellar dipoles and quadrupoles article pdf available in the astrophysical journal 7601 september 2012 with 35 reads. Indication of the hanle effect by comparing the scattering. It is said that the hanle effect is a type of level crossing experiment. Spin transport and hanle effect in silicon nanowires using. The coherent population trapping preparation is examined by means of a hanle effect configuration. We compare theoretical modeling with experimental data from driftdominated silicon spintransport devices, illustrating the nontrivial consequences of employing oblique magnetic fields due to misalignment or intentional, fixed inplane field components. Hanle effect spectra have been observed for a 1 ii pn. The theory of the hanle effect is used to interpret the linear polarization measured in a number of spectral lines on the solar disk near the heliographic north and south poles, in search for a turbulent magnetic field in the solar atmosphere. The effect is observed optically in an increase in the degree of.
Spontaneous emission of the microwave transition 37p 32 yields 37s 12 at 70. Hanle valley, valley containing hanle village, observatory and monastery. The hanle effect for the 3 2 s 1 2 3 2 p 1 2 transition. The combined use of hanle effect and optical pumping then permits one to measure magnetic fields as small as 10. We give a general proof of the \ \sqrt \in \law for the surface value of the source function and apply it to resonance polarization and hanle effect. The hanle effect and levelcrossing spectroscopyan introduction. We demonstrate a technique for continuous tuning of the hanle effect from electromagnetically induced transparency eit to electromagnetically induced absorption eia by changing the. Microwave hanle effect has been studied in sodium rydberg atoms for the first time. This is a standard spintronics tool and it gives access to. The hanle effect signal for the 0 band is fitted to a calculated signal, determining a radiative lifetime for the band of 227 70 ns. Pdf hanle effect for stellar dipoles and quadrupoles.
We study the shape of the coherent backscattering cbs cone obtained when resonant light illuminates a thick cloud of lasercooled rubidium atoms in presence. Pdf the hanle effect is the modification by the local magnetic field of the linear polarization parameters of a spectral line. Hanle effect measurement of the lifetime of the a 1ii state. I am most pleased and, in a way, i feel honored to write the foreword for the book the hanle effect and levelcrossing spectroscopy, which covers such a very wide range of applications not only in the initial areas of atomic and molecular physics.
The experimental results are compared with the theoretical predictions of two calculations, the first one considering only the steadystate regime, the second. Good agreement with the theoretical calculations has been found. The hanle effect, also known as zerofield level crossing, is a reduction in the polarization of. Hanle effect in transport through quantum dots coupled to ferromagnetic leads. Hanle effect measurement of the lifetime of the a 1ii. Spatial variation of dynamic nuclear spin polarization. An optical analogue of the hanle effect has been recently. The hanle effect has played a major role in the development of atomic physics and, more generally, of quantum. The derived formula is, in particular, supposed to be used. Spin transport and the hanle effect in organic spintronics spin transport and the hanle effect in organic spintronics yu, z. Experimental results from ca atomic beam optical frequency standard with electronshelving method show that a. The experimental results are compared with the theoretical predictions of two calculations, the first one considering only the steady. We give a general proof of the \ \sqrt \in \law for the surface value of the source function and apply it.
Pdf hanle effect with angledependent partial redistribution. Electrical investigation of the oblique hanle effect in ferromagnet. Pn is generated in a microwave discharge and flowed into a fluorescence cell where it is optically excited by a pn emission lamp. Here we address the problem of the diagnostics of weak magnetic fields in the solar photosphere and chromosphere by means of their hanle effect in some selected absorption lines. Enhanced absorption hanle effect in the configuration of. Hanle effect in transport through quantum dots coupled. This interaction needs to be taken into account in the analysis of experimental data, particularly in extracting the spin lifetime and its variation with different parameters temperature, doping concentration. We have solved a problem of the hanle effect for the hydrogen lyman. Pdf spin hanle effect in mesoscopic superconductors. The spin hall effect is a relativistic spinorbit coupling phenomenon, which can be used to electrically generate or detect spin currents in nonmagnetic systems.
The inverted hanle effect serves as experimental signature. Download fulltext pdf download fulltext pdf download fulltext pdf tuning of the hanle effect from eit to eia using spatially separated probe and control beams. The hanle effect, also known as zerofield level crossing, is a reduction in the polarization of light when the atoms emitting the light are subject to a magnetic field in a particular direction, and when they have themselves been excited by polarized light experiments which utilize the hanle effect include measuring the lifetime of excited states, and detecting the presence of magnetic. Jun 19, 2015 the raw data for the 3t hanle measurements with the magnetic field applied out of plane normal hanle effect, blue trace and in plane inverted hanle effect, red trace are shown in fig. Resonance polarization and hanle effect springerlink. Volume 60a, number 5 physics letters 21 march 1977 the hanle effect for the 3 2 3 22 transition of sodium au. Oblique hanle effect in semiconductor spin transport devices. Analytical solution of the hanle effect in view of clasp.
This is a weak zeeman effect that operates when the zeeman splitting is roughly comparable to the natural line broadening. The hanle effect and levelcrossing spectroscopy giovanni. We consider the coherent population trapping phenomenon in a thermal sodium atomic beam. The raw data for the 3t hanle measurements with the magnetic field applied out of plane normal hanle effect, blue trace and in plane inverted hanle effect, red trace are shown in. Spin precession and dephasing hanle effect provides an unambiguous means to establish the presence of spin transport in semiconductors. Although the physical processes and the theoretical framework described here are of interest for applications in a variety of astrophysical contexts e. In this case, the vapor of an eveneven isotope of mercury, e. The hanle depolarization is separated from a number of other effects, including collisional depolarization and scattering geometry. Here, we report an experimental observation of anomalous hanle effect in individual selfassembled inasgaas quantum dots where we find that a sizeable photocreated electron spin polarization can be. Here, we report an experimental observation of anomalous hanle effect in individual selfassembled inasgaas quantum dots where we find that a sizeable photocreated electron spin polarization can be maintained in transverse.
The hanle effect and its use for the measurements of very. The effect is observed optically in an increase in the degree of depolarization of the resonance fluorescence. Considering the strong inhomogeneous spatial polarization and intensity distribution of spontaneous decay fluorescence due to the hanle effect, we propose and demonstrate a universe hanle detection configuration of electronshelving method for optical clocks. The alternative tool is the hanle effect, a coherence phenomenon discovered 4. Burgmans philips research laboratories, eindhoven, the netherlands received 16 february 1977 experimental results are reported for the hanle effect on the 3 2s112 3 2p1,2 transition of sodium at vapour densities between i09 and 1012 atcm3. Pdf the hanle effect as diagnostic tool for turbulent magnetic.
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