Related papers: Persistent Fluctuating Superconductivity and Planc…
We report $^{125}$Te nuclear magnetic resonance and $^{181}$Ta nuclear quadrupole resonance studies on single-crystal Ta$_{4}$Pd$_{3}$Te$_{16}$, which has a quasi-one-dimensional structure and superconducts below $T_{\rm c}=4.3$ K.…
Understanding the roles of disorder and superconducting phase fluctuation in superconductivity has been a long-standing challenge. For example, while the phase fluctuation is expected to destroy the superconductivity of intrinsically…
A central challenge for understanding unconventional superconductivity in most strongly correlated electronic materials is their complicated band structure and presence of competing orders. In contrast, quasi-two-dimensional organic spin…
Superfluidity and superconductivity are genuine many-body manifestations of quantum coherence. For finite-size systems the associated pairing gap fluctuates as a function of size or shape. We provide a parameter free theoretical description…
Charge density waves are a common occurrence in all families of high critical temperature superconducting cuprates. Although consistently observed in the underdoped region of the phase diagram and at relatively low temperatures, it is still…
We propose a theoretical description of the superconducting state of under- to overdoped cuprates, based on the short coherence length of these materials and the associated strong pairing fluctuations. The calculated $T_c$ and the zero…
In many classes of unconventional superconductors, the question of whether the superconductivity is enhanced by the quantum-critical fluctuations on the verge of an ordered phase remains elusive. One of the most direct ways of addressing…
The anomalous transport and thermodynamic properties in the quantum-critical region, in the cuprates, and in the quasi-two dimensional Fe-based superconductors and heavy-fermion compounds, have the same temperature dependences. This can…
The possibility of driving phase transitions in low-density condensates through the loss of phase coherence alone has far-reaching implications for the study of quantum phases of matter. This has inspired the development of tools to control…
The recent discovery and subsequent developments of FeAs-based superconductors have presented novel challenges and opportunities in the quest for superconducting mechanisms in correlated-electron systems. Central issues of ongoing studies…
An overview of the momentum and frequency dependence of effective electron-electron interactions which favor electronic instability to a superconducting state in the angular-momentum channel $\ell$ and the properties of the interactions…
We show that an array of Josephson coupled Cooper paired planes can never have long range phase coherence at any finite temperature due to an infrared divergence of phase fluctuations. The phase correlations decay in a slow enough manner…
We study fluctuation conductivity in a single crystal of BaFe$_{1.9}$Ni$_{0.1}$As$_2$ superconductor ($T_c$ = 20 K) as a function of temperature and applied magnetic field. Magneto-conductivity curves, $\Delta \sigma$ vs. $T$, were analyzed…
In underdoped cuprates fluctuations of the phase of the superconducting order parameter play a role due to the small superfluid density. We consider the effects of phase fluctuations assuming the exchange of spin fluctuations to be the…
Superconducting properties of metallic nano-wires may strongly depend on specific experimental conditions. Here we consider a setup where superconducting phase fluctuations are restricted at one point inside the wire and equilibrium…
We present a systematic study of the nematic fluctuations in the iron chalcogenide superconductor Fe$_{1+y}$Te$_{1-x}$Se$_{x}$ ($0 \leq x \leq 0.53$) using the elastoresistivity technique. Near $x = 0$, in proximity to the double-stripe…
Disordered thin films close to the superconducting-insulating phase transition (SIT) hold the key to understanding quantum phase transition in strongly correlated materials. The SIT is governed by superconducting quantum fluctuations, which…
Fluctuation spectroscopy is used to investigate the organic bandwidth-controlled Mott system $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl. We find evidence for percolative-type superconductivity in the spatially inhomogeneous coexistence region…
In underdoped cuprates, T_c is thought to be determined by Cooper pair phase fluctuations because of the small superfluid density n_s. Experimentally, T_c is found to scale with n_s. The fluctuation-exchange approximation (FLEX) in its…
We review some recent developments in the field of quasi-one-dimensional superconductivity. We demonstrate that low temperature properties of superconducting nanowires are essentially determined by quantum fluctuations. Smooth (Gaussian)…