Incoherent Landau-Zener-Stückelberg transitions in single-molecule magnets

Physical Review B - Condensed Matter and Materials Physics

Volumn 79, Issue 10, 2009, Pages

  Vijayaraghavan, Avinash ^a   Garg, Anupam ^a  

^a NORTHWESTERN UNIVERSITY   (United States)

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EID: 64849098701     PISSN: 10980121     EISSN: 1550235X     Source Type: Journal    
DOI: 10.1103/PhysRevB.79.104423     Document Type: Article

References (39)

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39. Even though we do not need it to find /i ηi, the argument that follows provides still more support for our approach. The exp (-b t 12 2) behavior of |F| max can be understood if we note that the weight of the delta functions in the replacements 3 and 17 should be multiplied by another factor (1-Δ | t12 | /π) because the integrals over Ωi- begin from Δ, not 0. (This is readily seen by performing the integrals from 0 to, and from 0 to Δ, and subtracting.) When we make these changes, and fix c according to Eq. 31, we find S1 + S2 - S3 =b | Δ t12 | 2, with b=2.02 Edm / Eb, or just 2.02 if Edm = Eb. Our numerical fits yield b∼2.1-2.8, which is close enough given the crudeness of our estimates.