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This is the most complete handbook on the quantum theory of angular momentum. Containing basic definitions and theorems as well as relations, tables of formula and numerical tables which are essential for applications to many physical problems, the book is useful for specialists in nuclear and particle physics, atomic and molecular spectroscopy, plasma physics, collision and reaction theory, quantum chemistry, etc. The authors take pains to write many formulae in different coordinate systems thus providing users with added ease in consulting this book. Each chapter opens with a comprehensive list of its contents to ease the search for any information needed later. New results relating to different aspects of the angular momentum thoery are also included. Containing close to 500 pages this book also gathers together many useful formulae besides those related to angular momentum. The book also compares different notations used by previous authors.

FORTRAN 4 subroutines for coupling coefficients and matrix elements in quantum mechanical theory of angular momentum

A study of magneto-transport through quantum dots is presented. The model allows to analyze tunnelling both from bulk-like contacts and from 2D accumulation layers. The fine features in the I-V characteristics due to the quantum dot states are known to be shifted to different voltages depending upon the value of the magnetic field. While this effect is also well reproduced by our calculations, in this work we concentrate on the amplitude of each current resonance as a function of the magnetic field. Such amplitudes show oscillations reflecting the variation of the density of states at the Fermi energy in the emitter. Furthermore the amplitude increases as a function of the magnetic field for certain features while it decreases for others. In particular we demonstrate that the behaviour of the amplitude of the current resonances is linked to the value of the angular momentum of each dot level through which tunnelling occurs. We show that a selection rule on the angular momentum must be satisfied. As a consequence, tunnelling through specific dot states is strongly suppresses and sometimes prohibited altogether by the presence of the magnetic field. This will allow to extract from the experimental curves detailed information on the nature of the quantum dot wavefunctions involved in the electronic transport. Furthermore, when tunnelling occurs from a 2D accumulation layer to the quantum dot, the presence of a magnetic field hugely increases the strength of some resonant features. This effect is predicted by our model and, to the best of our knowledge, has never been observed.

A study of magneto-transport through quantum dots is presented. The model allows to analyze tunnelling both from bulk-like contacts and from 2D accumulation layers. The fine features in the I-V characteristics due to the quantum dot states are known to be shifted to different voltages depending upon the value of the magnetic field. While this effect is also well reproduced by our calculations, in this work we concentrate on the amplitude of each current resonance as a function of the magnetic field. Such amplitudes show oscillations reflecting the variation of the density of states at the Fermi energy in the emitter. Furthermore the amplitude increases as a function of the magnetic field for certain features while it decreases for others. In particular we demonstrate that the behaviour of the amplitude of the current resonances is linked to the value of the angular momentum of each dot level through which tunnelling occurs. We show that a selection rule on the angular momentum must be satisfied. As a consequence, tunnelling through specific dot states is strongly suppresses and sometimes prohibited altogether by the presence of the magnetic field. This will allow to extract from the experimental curves detailed information on the nature of the quantum dot wavefunctions involved in the electronic transport. Furthermore, when tunnelling occurs from a 2D accumulation layer to the quantum dot, the presence of a magnetic field hugely increases the strength of some resonant features. This effect is predicted by our model and, to the best of our knowledge, has never been observed.

56 p. 21 cm

We consider in a quantum field theory framework the effects of a classical magnetic field on the spin and orbital angular momentum (OAM) of a free electron. We derive formulae for the changes in the spin and OAM due to the introduction of a general classical background field. We consider then a constant magnetic field, in which case the relevant expressions of the effects become much simpler and conversions between spin and OAM become readily apparent. An estimate of the expectation values for a realistic electron state is also given. Our findings may be of interest to researchers in spintronics and the field of quantum biology, where electron spin has been implicated on macroscopic time and energy scales.

We consider in a quantum field theory framework the effects of a classical magnetic field on the spin and orbital angular momentum (OAM) of a free electron. We derive formulae for the changes in the spin and OAM due to the introduction of a general classical background field. We consider then a constant magnetic field, in which case the relevant expressions of the effects become much simpler and conversions between spin and OAM become readily apparent. An estimate of the expectation values for a realistic electron state is also given. Our findings may be of interest to researchers in spintronics and the field of quantum biology, where electron spin has been implicated on macroscopic time and energy scales.