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Commensurate Fluctuations in the Pseudogap and Incommensurate spin-Peierls Phases of TiOCl

J. P. Clancy·B. D. Gaulin·K. C. Rule·J. P. Castellan·F. C. Chou
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Abstract

X-ray scattering measurements on single crystals of TiOCl reveal the presence of commensurate dimerization peaks within both the incommensurate spin-Peierls phase and the so-called pseudogap phase above T_c2. This scattering is relatively narrow in Q-space indicating long correlation lengths exceeding ~ 100 A below T* ~ 130 K. It is also slightly shifted in Q relative to that of the commensurate long range ordered state at the lowest temperatures, and it coexists with the incommensurate Bragg peaks below T_c2. The integrated scattering over both commensurate and incommensurate positions evolves continuously with decreasing temperature for all temperatures below T* ~ 130 K.

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J. P. Clancy, B. D. Gaulin, K. C. Rule, J. P. Castellan, F. C. Chou. 2007-02-17. Commensurate Fluctuations in the Pseudogap and Incommensurate spin-Peierls Phases of TiOCl. https://doi.org/10.1103/physrevb.75.100401

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