High-magnetic-field phase diagram of a quasi-one-dimensional metal

Abstract

We present a unique high magnetic field phase of the quasi-one dimensional organic conductor (TMTSF) 2 ClO 4 . This phase, termed "Q-ClO 4 ", is obtained by rapid thermal quenching to avoid ordering of the ClO 4 anion.The magnetic field dependent phase of Q-ClO 4 is distinctly different from that in the extensively studied annealed material. Q-ClO 4 exhibits a spin density wave (SDW) transition at ≈ 5 K which is strongly magnetic field dependent. This dependence is well described by the theoretical treatment of Bjelis and Maki. We show that Q-ClO 4 provides a new B-T phase diagram in the hierarchy of low-dimensional organic metals (one-dimensional towards two-dimensional), and describe the temperature dependence of the of the quantum oscillations observed in the SDW phase.

Coexistence of superconductivity and spin-density wave in(TMTSF)2ClO4: Spatial structure of the two-phase state

“…The former depends on the orderinginduced band-splitting V , namely, SDW onset at high temperatures reflects low degree of ordering 20,22 . Typical values of transition temperatures achieved after quenching in our measurements, 6−6.5 K, are close to those observed experimentally by other groups 19,41 . The width of SDW transition is small for high quench rates and T Q -temperatures; it increases as T Q decreases.…”

New SDW phases in quasi-one-dimensional systems dimerized in the transverse direction

“…The critical temperature of this zero-field transition increases with the cooling rate up to the value of about 5.5 K for quenched samples. [2,3] It is believed that this strong dependence of the SDW ordering on the cooling rate and its absence in carefully relaxed samples are related to the fact that (TMTSF) 2 being the inter-chain distance, as shown on Fig. 1.…”

“…The critical temperature of this zero-field transition increases with the cooling rate up to the value of about 5.5 K for quenched samples. [2,3] It is believed that this strong dependence of the SDW ordering on the cooling rate and its absence in carefully relaxed samples are related to the fact that (TMTSF) 2 ClO 4 in its ground state acquires a long range order of anion molecules ClO 4 . This ordering sets up at the temperatures up to about 24K, inducing a doubling of the unit cell perpendicularly to chains, with the new lattice constant d = 2b, b being the inter-chain distance, as shown on Fig.…”

Magnetic oscillations and field-induced spin-density waves in(TMTSF)2ClO4

“…Each state N is split by δ in a way that components with the tilt −δ have the statistical weight |µ k | 2 (|a N | 2 + |b N | 2 ) and the ones with the tilt +δ have the weight |ν k | 2 (|b N | 2 + |â N | 2 ). Green function Ψ(x, p)Ψ † (x ′ , p) is easily constructed using transformation (5) and knowing that ΦΦ…”