It has been shown that a tight-binding model describes, at least qualitatively, the main features of the magnetic-field-induced cascade of spin-density-wave subphases in Bechgaard salts. Here we work out an analytical method which allows a complete and rigorous description of the ordered subphases for any magnetic field and temperature. Comparisons with previous approximations and numerical solutions are discussed within the mean-field approximation.

• Received 27 May 1987

DOI:https://doi.org/10.1103/PhysRevB.37.1913