As this is a relatively new area we will focus on the diagnostic methods and. 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. 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. Pdf the hanle effect is the modification by the local magnetic field of the linear polarization parameters of a spectral line. 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 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. 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. The coherent population trapping preparation is examined by means of a hanle effect configuration. Pdf the hanle effect applied to magnetic field diagnostics. 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.
Spatial variation of dynamic nuclear spin polarization. Hanle valley, valley containing hanle village, observatory and monastery. It is said that the hanle effect is a type of level crossing experiment. Good agreement with the theoretical calculations has been found. Spin precession and dephasing hanle effect provides an unambiguous means to establish the presence of spin transport in semiconductors. The experimental results are compared with the theoretical predictions of two calculations, the first one considering only the steady. 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. Q and u measure the intensity of linearly polarized light relative to two axes. The hanle effect and the diagnostics of turbulent magnetic. The hanle effect and its use for the measurements of very small magnetic fields. The hanle effect for the 3 2 s 1 2 3 2 p 1 2 transition of sodium. The hanle effect and its use for the measurements of very small magnetic. The hanle effect describes suppression of spin polarization due to precession in a magnetic field.
Hanle effect in transport through quantum dots coupled. Spin transport and hanle effect in silicon nanowires using. Hanle effect measurement of the lifetime of the a 1ii state. Electrical investigation of the oblique hanle effect in ferromagnet. 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. Experimental results from ca atomic beam optical frequency standard with electronshelving method show that a. 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. Calculations on the hanle effect with phase and amplitude. For laser radiation with linear polarization orthogonal to the applied magnetic field, the hanle signal is characterized by narrow bright resonances at low. 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. 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. The hanle effect is the modification by the local magnetic field of the linear polarization parameters of a spectral line.
This is a weak zeeman effect that operates when the zeeman splitting is roughly comparable to the natural line broadening. Indication of the hanle effect by comparing the scattering. The hanle effect and its use for the measurements of very. The polarized line transfer equation for the hanle effect is solved in the framework of an exact partial. 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.
Spontaneous emission of the microwave transition 37p 32 yields 37s 12 at 70. The hanle effect applied to magnetic field diagnostics. Although the physical processes and the theoretical framework described here are of interest for applications in a variety of astrophysical contexts e. 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. Spin transport and the hanle effect in organic spintronics spin transport and the hanle effect in organic spintronics yu, z. The hanle effect and levelcrossing spectroscopy giovanni. Timedependent behavior of linear polarization in unresolved. 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. The derived formula is, in particular, supposed to be used. 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. Download pdf 569 kb abstract this article presents an introduction to optical pumping, atomic polarization and the hanle effect in weakly magnetized stellar atmospheres. Pdf tuning of the hanle effect from eit to eia using. Hanle effect spectra have been observed for a 1 ii pn. We consider the coherent population trapping phenomenon in a thermal sodium atomic beam.
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. 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. 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. We give a general proof of the \ \sqrt \in \law for the surface value of the source function and apply it. 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. The hanle effect for the 3 2s12 3 2p12 transition of sodium. Enhanced absorption hanle effect in the configuration of. 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. Additionally, a magnetic field may perturb and modify the line scattering polarization signals through the hanle effect. Microwave hanle effect has been studied in sodium rydberg atoms for the first time. 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 experimental results are compared with the theoretical predictions of two calculations, the first one considering only the steadystate regime, the second.
The hanle effect is measured to study spin relaxation in ch 3 nh 3 pbbr 3 film, yielding a spin lifetime of. However, when spin dephasing is very strong, hanle effect in a uniaxial magnetic field can be impossible to measure. The hanle effect and levelcrossing spectroscopyan introduction. The hanle effect for the 3 2 s 1 2 3 2 p 1 2 transition. Geometric dephasinglimited hanle effect in longdistance. 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. As this is a relatively new area we will focus on the. Spin transport and the hanle effect in organic spintronics. Pdf spin hanle effect in mesoscopic superconductors. Scattering polarization and hanle effect in stellar atmospheres with. In this case, the vapor of an eveneven isotope of mercury, e. 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.
Analytical solution of the hanle effect in view of clasp and. 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. Circularly polarized photoluminescence and hanle effect. Pn is generated in a microwave discharge and flowed into a fluorescence cell where it is optically excited by a pn emission lamp. Coherent population trapping with losses on the sodium d1. Hanle effect in transport through quantum dots coupled to ferromagnetic leads. The alternative tool is the hanle effect, a coherence phenomenon discovered 4 by wilhelm hanle in 1924. Polarization and the hanle effect polarizationis measuredin termsof the fourstokesvectorcomponents, i, q, u and v. This is a standard spintronics tool and it gives access to. The hanle effect as a diagnostic of magnetic fields in. The hanle depolarization is separated from a number of other effects, including collisional depolarization and scattering. The spin hall effect is a relativistic spinorbit coupling phenomenon, which can be used to electrically generate or detect spin currents in nonmagnetic systems. 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.
Monographs that deal with atomic physics and polarized radiative transfer provide excellent treatments of the hanle effect. The field of organic spintronics has taken off since the discovery of large magnetoresistance in thick organic spin valves osvs. It is shown that optical pumping can be used to create alignment of states. Volume 60a, number 5 physics letters 21 march 1977 the hanle effect for the 3 2 3 22 transition of sodium au. The hanle e ect is a powerful diagnostic tool for the measurement of weak magnetic elds, deterministic or turbulent sten o 1978. The effect is observed optically in an increase in the degree of depolarization of the resonance fluorescence. Pdf the hanle effect is calculated for a random magnetic field characterized by. The hanle depolarization is separated from a number of other effects, including collisional depolarization and scattering geometry. The effect is observed optically in an increase in the degree of. 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. The hanle effect light from a secondary mercury source is shown onto a primary mercury vapor cell located in a slowly varying magnetic field. 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. We demonstrate a technique for continuous tuning of the hanle effect from electromagnetically induced transparency eit to electromagnetically induced absorption eia by changing the. The influence of weak localization on hanle effect in a twodimensional system with spinsplit spectrum is considered.
If energy levels are split in an external magnetic eld, then in the range from weak to mediumstrength elds, the levels can indeed cross. The hanle effect, also known as zerofield level crossing, is a reduction in the polarization of. 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. We study the shape of the coherent backscattering cbs cone obtained when resonant light illuminates a thick cloud of lasercooled rubidium atoms in presence. Vector integral equations for polarized transfer, are known to be useful for analytical work, numerical work and phenomenological analyses.
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. If energy levels are split in an external magnetic field, then. The nonlinear hanle effect and its applications to laser physics. The inverted hanle effect serves as experimental signature. We have solved a problem of the hanle effect for the hydrogen lyman. 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. Pdf the hanle effect as diagnostic tool for turbulent magnetic. Analytical solution of the hanle effect in view of clasp. 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. Hanle effect measurement of the lifetime of the a 1ii.
The thickness of organic films 100 nm in these osvs should preclude direct. Non perturbative calculation for a j 0 to j 1 transition. Pdf hanle effect with angledependent partial redistribution. 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. For laser radiation with linear polarization orthogonal to the applied magnetic field, the hanle signal is. Hanle effect is ubiquitous in the study of spinrelated phenomena and has been used to determine spin lifetime, precession and transport in semiconductors.
An optical analogue of the hanle effect has been recently. Hanle effect with angledependent partial redistribution. Download fulltext pdf hanle effect for stellar dipoles and quadrupoles article pdf available in the astrophysical journal 7601 september 2012 with 35 reads. Tuning of the hanle effect from eit to eia using spatially. The existence of a cpl that is dependent on the helicity of the excitation laser, and the unexpectedly long spin lifetime. The alternative tool is the hanle effect, a coherence phenomenon discovered 4. 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. Pdf the hanle effect and level crossing spectroscopy in rb. The combined use of hanle effect and optical pumping then permits one to measure magnetic fields as small as 10.