Pressure Effect on the Charge-Density Waves and the Superconductivity in NbSe₃

Superconductivity at 5.2 K in ZrTe3polycrystals and the effect of Cu and Ag intercalation

“…In this context, it is to be mentioned that in NbSe 3 single crystals, superconductivity was never observed down to 50 mK and it is argued that a very high pressure is required for inducing superconductivity, the condition for which exist in the grain boundaries of polycrystalline sample. [14,23,24] In conclusion, the polycrystalline samples of ZrTe 3 are found to superconduct at enhanced temperature of 5.2 K. The volume of superconducting fraction is less and we speculate that like the CDW state, which is observed in 'a' and 'c' directions only, superconductivity also sets in only along these directions in the remnant part of the Fermi surface, and therefore is not a bulk feature. Though it is filamentary in nature, It is akin to the effect of external pressure on T c in ZrTe 3 single crystal.…”

“…The effect of pressure on CDW is akin to that of the doping of the foreign atoms in the lattice, where redistribution of charge leads to the reduction in the nested FS. [13,14] Previous studies have reported the presence of filamentary SC in single crystalline ZrTe 3 with T c < 2 K, with weakly coupled SC filaments aligned parallel to the 'a' axis with the spacing of 4 nm. [6,7] These SC filaments run parallel to the 'a' axis, perpendicular direction of triangular prismatic chain of ZrTe 3 .…”

Pressure effect on large magnetoresistance in the lower charge-density-wave transition ofNbSe3

“…Pressures were estimated from the pressure dependence of T c1 and T c2 in NbSe 3 based on a previous result. 16 Figure 1 shows the temperature dependence of the resistance of NbSe 3 in the magnetic fields at ambient pressure.…”

“…On the other hand, although the P-T-H phase diagram of CDW in NbSe 3 is not yet settled, it is well known that in zero magnetic field the T c2 -CDW phase of NbSe 3 is suppressed totally by pressure above the critical pressure of 7.5 kbar. 16 It is important to investigate magnetic-field effects on CDW of NbSe 3 in the region near the critical pressure in order to see whether the CDW order parameter is changed by the magnetic field.…”

Experimental consequences of quantum critical points at high temperatures

“…There are at least two other compounds that show a behavior with pressure similar to that of Cr metal. The one dimensional transition metal trichalcogenide NbSe 3 , a well-studied charge density wave (CDW) compound 18,19,20 and β − Na 0.33 V 2 O 5 , a material with a charge order (CO) 21 . As 8 shown on the left panel of Fig.…”