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Energy levels for a pair of ant i ferromagnetically coupled

Energy levels for a pair of ant i ferromagnetically coupled S = 5/2 spins. The arrows show the transitions between the levels that are allowed in inelastic neutron scattering events. Note that in a single scattering act the total spin can change only by  S = ± 1 (can you

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Energy levels for a pair of ant i ferromagnetically coupled

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  1. Energy levels for a pair of antiferromagnetically coupled S = 5/2 spins. The arrows show the transitions between the levels that are allowed in inelastic neutron scattering events. Note that in a single scattering act the total spin can change only by S = ±1 (can you explain why?) tot

  2. Schematic of a time-of-flight inelastic neutron scattering spectrometer − a perfect tool for investigating dispersionless excitations in solid: Disk chopper

  3. This is one of the instruments we use:

  4. The idea worked, and even though the FM coupling induced by holes was weak, the information the measurement yielded was really valuable

  5. People are trying to figure out the rules that govern the Mn-Mn NN exchange in dilute alloys derived from the II-VI compound family (ZnO, ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, HgTe).

  6. E=0.158 meV Zn1-xMnxTe (x = 2%)=4.8Å, T= 40K • J1atm= -0.795 meV • J4Katm=-0.836 meV • 5% Energy Shift • 0.49% Lattice Compression • |2|1 Transition

  7. Our data show that the “tendency line” based on the entire family definitely is not a universal characteristic, because the J(r) depen- dence in individual compounds from the (II,Mn)-VI family is deci- dedly steeper than it predicts (individuals showing lack of respect for family values?)

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