Spin-peierls systems in magnetic field: Phase transition from dimerized to soliton lattice state

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

“…For CuGeO 3 it was shown that the lattice distortion rapidly approaches a nearly sinusoidal one above the critical field [18] so that one should not expect higher-n modes to be observable. The field dependence of the incommensurability vector Q M (H) above the critical field H c was studied theoretically based on the XY model [29] …”

Far-infrared spectroscopy in the spin-Peierls compoundCuGeO3under high magnetic fields

“…The universal curve is well described by the function 1/ ln[8H C /(H − H C )], which is predicted by the mean field theory. 33 The right scale was adjusted to fit ∆ω to the universal curve. It is obvious that ∆ω is also well described by the same universal curve.…”

Synchrotron X-ray diffraction measurements in applied magnetic fields

“…The M (or incommensurate, IC) phase is in a magnetized state with an incommensurate lattice distortion whose wave vector changes with H [12][13][14]. The magnetized chains consist of singlet dimers separated by a domain wall forming a soliton lattice [14]. Direct evidence of lattice dimerization has been obtained from an X-ray diffraction study on an organic spin-Peierls compound, TTF-CuBDT [15] in the 1970s.…”

“…In the following, we discuss the above finding based on the theory developed by Buzdin et al [14]. The T ¼ 0 limit of dl is obtained by minimizing the thermodynamic potential with respect to 1=L; where, L is given in Ref.…”

“…In the uniform (U) phase, the system is in an S ¼ 1 2 1D HAF state without lattice distortion. The M (or incommensurate, IC) phase is in a magnetized state with an incommensurate lattice distortion whose wave vector changes with H [12][13][14]. The magnetized chains consist of singlet dimers separated by a domain wall forming a soliton lattice [14].…”