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تسجيل مستخدم جديدUnconventional spin density wave in Bechgaard salt (TMTSF)2NO3
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Among many Bechgaard salts, TMTSF2NO3 exhibits very anomalous low temperature properties. Unlike conventional spin density wave (SDW), TMTSF2NO3 undergoes the SDW transition at $T_SDWapprox 9.5$ K and the low temperature quasiparticle excitations are gapless. Also, it is known that TMTSF2NO3 does not exhibit superconductivity even under pressure, while FISDW is found in TMTSF2NO3 only for P=8.5 kbar and B>20 T. Here we shall show that both the angle dependent magnetoresistance data and the nonlinear Hall resistance of TMTSF2NO3 at ambient pressure are interpreted satisfactory in terms of unconventional spin density wave (USDW). Based on these facts, we propose a new phase diagram for Bechgaards salts.
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Among known Bechgaard and Fabre salts (TMTSF)2NO3 is unique since it never becomes superconducting even under pressure. Also, though (TMTSF)2NO3 undergoes the spin density wave (SDW) transition, the low temperature transport is semimetallic and gaple
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It is well documented that SDW in (TMTSF)2PF6 undergoes another phase transition at T*approx 4K, though the nature of the new low temperature phase is controversial. We have shown recently that the new phase is well described in terms of unconvention
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Magnetoresistance measurements on the quasi one-dimensional organic conductor (TMTSF)_2PF_6 performed in magnetic fields B up to 16T, temperatures T down to 0.12K and under pressures P up to 14kbar have revealed new phases on its P-B-T phase diagram.
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