Bloch equations
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Wigner-Eckart theorem in quantum mechanics proves that particle's magnetic moment is collinear with it's angular moment so that: | Wigner-Eckart theorem in quantum mechanics proves that particle's magnetic moment is collinear with it's angular moment so that: | ||
- | <math>M = \gamma J</math>, | + | <math>\displaystyle M = \gamma J</math>, |
where γ is the scalar quantity called [[gyromagnetic ratio]] of the particle. | where γ is the scalar quantity called [[gyromagnetic ratio]] of the particle. |
Revision as of 01:22, 7 July 2009
Bloch equation describes evolution of classical magnetic moment in the magnetic field.
A particle with a magnetic moment M in the magnetic field B will experience change of its mechanical angular moment J, i.e. torque = dJ/dt.
Wigner-Eckart theorem in quantum mechanics proves that particle's magnetic moment is collinear with it's angular moment so that:
,
where γ is the scalar quantity called gyromagnetic ratio of the particle.
Therefore we have expression (known as Bloch Equation):