Acoustic paramagnetic resonance

In acoustics, acoustic paramagnetic resonance (APR) is a phenomenon of resonant absorption of sound by a system of magnetic particles placed in an external magnetic field. It occurs when the energy of the sound wave quantum becomes equal to the splitting of the energy levels of the particles, the splitting being induced by the magnetic field. APR is a variation of electron paramagnetic resonance (EPR) where the acoustic rather than electromagnetic waves are absorbed by the studied sample. APR was theoretically predicted in 1952, independently by Semen Altshuler and Alfred Kastler,[1][2] and was experimentally observed by W. G. Proctor and W. H. Tanttila in 1955.[3][4]

  1. ^ Boris I. Kochelaev (1995). The beginning of paramagnetic resonance. World Scientific. p. 100. ISBN 981-02-2114-2.
  2. ^ S.A. Altshuler (1952). Soviet Physics Doklady (in Russian). 85: 1235.{{cite journal}}: CS1 maint: untitled periodical (link)
  3. ^ Proctor, W.; Tanttila, W. (1955). "Saturation of Nuclear Electric Quadrupole Energy Levels by Ultrasonic Excitation". Physical Review. 98 (6): 1854. Bibcode:1955PhRv...98Q1854P. doi:10.1103/PhysRev.98.1854.
  4. ^ S. A. Altshuler; B. I. Kochelaev; A. M. Leushin (1961). "Paramagnetic absorption of sound". Soviet Physics Uspekhi (in Russian). 75 (3): 459.