Electrical properties and phase transitions in superconducting quasi-one-dimensional chalcogenides In[sub x]Nb[sub 3]X[sub 4] (X = S, Se, and Te)

Journal Article · Thu Apr 01 04:00:00 EST 1993 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1006/jssc.1993.1128· OSTI ID:6265493

Ohtani, T; Sano, Y; Yokota, Y ^[1]

---

1. Okayama Univ. of Science (Japan)

Electrical properties and phase transitions were investigated in the quasi-one-dimensional ternary chalcogenides In[sub x]Nb[sub 3]X[sub 4] (X = S, Se, and Te; x = 0.5 for X = S, and 1.0 for X = Se and Te), with results indicating that the In[sub x]Nb[sub 3]Te[sub 4] system has two new kinds of phase transitions. Based on the values of the transition temperatures T[sub t], this system is classified into two groups, i.e., Group 1 samples with 0 [le] x < 0.55 having T[sub t] = [approx]40 and [approx]80 K, and Group 2 samples with 0.55 < x [le] 1.0 having T[sub t] = [approx]50 and [approx]140 K. Electron diffraction measurements showed the 140-K transition to be associated with a charge-density-wave (CDW) formation accompanied by the appearance of a superstructure that can be explained by the commensurate wave vectors q = ([+-]1/3a* + 1/3b*) + 4/9c*, which are slightly larger in the c* component as compared with those previously observed in Nb[sub 3]Te[sub 4] of q = [+-](1/3a* + 1/3b*) + 3/7c*. The increase in the c* component was interpreted as being caused by the increase in Fermi energy due to In insertion. Thermopower measurements on In[sub x]Nb[sub 3]Te[sub 4] showed the dominant carriers to be holes. In addition, the In[sub x]Nb[sub 3]Se[sub 3.84] system (0.40 [le] x [le] 1.0) showed a new CDW-like transition at [approx] 30 K. The superconducting critical temperature [Tc] of In[sub x]Nb[sub 3]X[sub 4] was increased by several degrees when the In content x was increased above 0.5. 27 refs., 10 figs., 1 tab.

• OSTI ID: 6265493
• Journal Information: Journal of Solid State Chemistry; (United States), Journal Name: Journal of Solid State Chemistry; (United States) Vol. 103:2; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure &amp; Phase Studies
360607 -- Other Materials-- Superconducting Properties-- (1992-)
CARRIERS
CHALCOGENIDES
CHARGE DENSITY
COHERENT SCATTERING
CRITICAL TEMPERATURE
DIFFRACTION
ELECTRICAL PROPERTIES
ELECTRON DIFFRACTION
ENERGY LEVELS
FERMI LEVEL
HOLES
INDIUM COMPOUNDS
INDIUM SELENIDES
INDIUM SULFIDES
INDIUM TELLURIDES
NIOBIUM COMPOUNDS
NIOBIUM SELENIDES
NIOBIUM SULFIDES
NIOBIUM TELLURIDES
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
REFRACTORY METAL COMPOUNDS
SCATTERING
SELENIDES
SELENIUM COMPOUNDS
STOICHIOMETRY
SULFIDES
SULFUR COMPOUNDS
SUPERCONDUCTORS
TELLURIDES
TELLURIUM COMPOUNDS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE