Naslov
Low- temperature thermodynamic investigation of the sulphur organic salts (TMTTF)2PF6 and (TMTTF)2Br: general aspects (I part)

Autori
Lasjaunias, J. C. ; Brison, J. P. ; Monceau, P. ; Starešinić, Damir ; Biljaković, Katica ; Carcel, C. ; Fabre, J. M.

Izvornik
JOURNAL OF PHYSICS-CONDENSED MATTER (0953-8984) 14 (2002); 837-947

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Spin-density-wave. Peierls compound cugeo3. Glass-transition. Phase. Heat. Charge. (tmtsf)(2)pf6. (tmtsf)2pf6. Impurities.

Sažetak
A detailed thermodynamical investigation of the quasi-one-dimensional sulphur-based organic salts (TMTTF)(2)PF6 and (TMTTF)(2)Br is presented in the temperature range from 30 mK to 7 K. In this part (part I), we consider the general aspects of the low-temperature specific heat of these materials in relationship with their ground states and we compare them with those previously measured for selenium members of the same family. All these compounds exhibit very similar thermodynamical behaviour, despite a variety of electronic ground states: spin-Peierls for (TMTTF)(2)PF6, commensurate antiferromagnetic spin modulation for (TMTTF)(2)Br, incommensurate spin-density wave for (TMTSF)(2)PF6 (TMTSF drop tetramethyltetraselenafulvalene). We show that the low-energy excitations which are predominant below 1 K have a similar character to that observed in glassy systems, at least on short timescales of measurements. The dynamical aspects of the non-equilibrium thermodynamics will be presented separately in the following part (part H).

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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