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Related papers: Analytical Study of the Spin Projection Operator

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We study the longitudinal spin polarization of a relativistic fluid of massive spin-1/2 particles undergoing a boost-invariant expansion in the longitudinal direction and rotating in the transverse plane. We express the polarization vector…

Nuclear Theory · Physics 2025-03-18 Nora Weickgenannt , Jean-Paul Blaizot

In spin-1 collective atomic systems, the spin and nematic-tensor operators constitute the su(3) Lie algebra whose su(2) subalgebras are shown to give two distinct classes of squeezing which are unitarily equivalent to spin squeezing and…

Quantum Physics · Physics 2013-10-02 Emi Yukawa , Masahito Ueda , Kae Nemoto

We present a general unifying theory for spin polarization decay due to the interplay of spin precession and momentum scattering that is applicable to both spin-1/2 electrons and spin-3/2 holes. Our theory allows us to identify and…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Dimitrie Culcer , Roland Winkler

We observe a spontaneous parity breaking bifurcation to a ferromagnetic state in a spatially trapped exciton-polariton condensate. At a critical bifurcation density under nonresonant excitation, the whole condensate spontaneously magnetizes…

Fabrication and optical characteristics of a spin light-emitting-diode (spin-LED) having dual spin-injection electrodes with anti-parallel magnetization configuration are reported. Alternating a current between the two electrodes using a…

Materials Science · Physics 2015-06-18 N. Nishizawa , K. Nishibayashi , H. Munekata

We address evolution of a spinor polariton condensate in radially periodic potentials. Such potentials allow for the observation of novel nonlinear excitations and support a variety of dynamically stable soliton states never demonstrated…

Mesoscale and Nanoscale Physics · Physics 2019-03-13 Dmitry A. Zezyulin , Yaroslav V. Kartashov , Dmitry V. Skryabin , Ivan A. Shelykh

We present a systematic study of the proton spin structure in terms of measurable parton distributions. For a transversely-polarizedproton, we derive a polarization sum rule from the leading generalized parton distributions appearing in…

High Energy Physics - Phenomenology · Physics 2012-10-18 Xiangdong Ji , Xiaonu Xiong , Feng Yuan

We outline a program for interpreting the higher-spin dS/CFT model in terms of physics in the causal patch of a dS observer. The proposal is formulated in "elliptic" de Sitter space dS_4/Z_2, obtained by identifying antipodal points in…

High Energy Physics - Theory · Physics 2019-12-03 Illan F. Halpern , Yasha Neiman

The interpretation of quantum mechanics due to Lande' is applied to the connection between wave mechanics and matrix mechanics. The connection between the differential eigenvalue equation and the matrix eigenvalue equation for an operator…

Quantum Physics · Physics 2007-05-23 Habatwa Vincent Mweene

Determining the spin of any new particle and measuring its couplings to other particles and/or itself are crucial in reconstructing the structure of any quantum field theory containing the particle. A general helicity formalism is employed…

High Energy Physics - Phenomenology · Physics 2019-03-05 Seong Youl Choi , Jae Hoon Jeong , Ji Ho Song

We have worked out covariant amplitudes for any two-body decay of a resonance with an arbitrary non-zero mass, which involves arbitrary integer spins in the initial and the final states. One key new ingredient for this work is the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Suh-Urk Chung , Jan Friedrich

The first part of the paper reviews applications of 2-spinor methods to relativistic qubits (analogies between tetrads in Minkowski space and 2-qubit states, qubits defined by means of null directions and their role for elimination of the…

Quantum Physics · Physics 2012-09-21 Marek Czachor

The spinor-helicity representations of massive and (partially-)massless particles in four dimensional (Anti-) de Sitter spacetime are studied within the framework of the dual pair correspondence. We show that the dual groups (aka "little…

High Energy Physics - Theory · Physics 2024-01-05 Thomas Basile , Euihun Joung , Karapet Mkrtchyan , Matin Mojaza

Spin 1 particle is investigated in 3-dimensional curved space of constant negative curvature. An extended helicity operator is defined and the variables are separated in a tetrad-based 10-dimensional Duffin--Kemmer equation in quasi…

Mathematical Physics · Physics 2012-05-02 E. M. Ovsiyuk , K. V. Kazmerchuk

We study the ground state properties of the spin-1/2 frustrated ferromagnetic J1-J2 Heisenberg model on the square lattice, employing projected BCS wavefunctions with spin-triplet pairings of the spinon fields as trial wavefunctions. Based…

Strongly Correlated Electrons · Physics 2011-10-18 Ryuichi Shindou , Seiji Yunoki , Tsutomu Momoi

We explain the finite as well as infinite degeneracy in the spectrum of a particular system of spin-1/2 fermions with spin-orbit coupling in three spatial dimensions. Starting from a generalized Runge-Lenz vector, we explicitly construct a…

Mesoscale and Nanoscale Physics · Physics 2014-03-12 S. M. Haaker , F. A. Bais , K. Schoutens

External driving of spinor degrees of freedom by magnetic or optical fields in quantum systems underpin many applications ranging from nuclear magnetic resonance to coherent state control in quantum computing. Although spinor polariton…

In this article, we extend the %Weyl-van der Waerden spinor technique for calculating helicity amplitudes to general massive fields of half-integer spins. We find that the little group generators can be represented as first-order…

High Energy Physics - Theory · Physics 2012-04-09 Gang Chen , Konstantin G. Savvidy

We study the production of a single resonance at the LHC and its decay into a pair of Z bosons. We demonstrate how full reconstruction of the final states allows us to determine the spin and parity of the resonance and restricts its…

High Energy Physics - Phenomenology · Physics 2010-05-12 Yanyan Gao , Andrei V. Gritsan , Zijin Guo , Kirill Melnikov , Markus Schulze , Nhan V. Tran

We present a proof that the operator norm of the commutator of certain spectral projections associated with spin operators converges to $\frac 1 2$ in the semiclassical limit. The ranges of the projections are spanned by all eigenvectors…

Mathematical Physics · Physics 2025-10-02 Ood Shabtai