Uwe S. Pracht

The Higgs mode in disordered superconductors close to a quantum phase transition

The Higgs mechanism is best known for generating mass for subatomic particles. Less well-known is that the idea originated in the study of superconductivity, and can be tested in the laboratory.

Enhanced Cooper pairing versus suppressed phase coherence shaping the superconducting dome in coupled aluminum nanograins

Uwe S. Pracht, ∗ Nimrod Bachar, 3, 4 Lara Benfatto, Guy Deutscher, Eli Farber, Martin Dressel, and Marc Scheffler 1. Physikalisches Institut, Universität Stuttgart, Germany Department of Quantum Matter Physics, University of Geneva, Switzerland Laboratory for Superconductivity and Optical Spectroscopy, Ariel University, Israel Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Israel ISC-CNR and Department of Physics, Sapienza University of Rome, Italy (Dated: August 20, 2015)

Direct observation of the superconducting gap in thin film of titanium nitride using terahertz spectroscopy

We report on the charge carrier dynamics of superconducting titanium nitride (TiN) in the frequency range 90–510 GHz (3–17 cm−1). The experiments were performed on an 18-nm thick TiN film with a critical temperature of Tc=3.4 K. Measurements were carried out from room temperature down to 2 K, and in magnetic fields up to B=7 T. We extract the real and imaginary parts of the complex conductivity σ as a function of frequency and temperature, directly providing the superconducting energy gap 2Δ. Further analysis yields the superconducting London penetration depth λL. The findings as well as the normal-state properties strongly suggest conventional BCS superconductivity, underlined by the ratio 2Δ(0)/kBTc=3.44. Detailed analysis of the charge carrier dynamics of the silicon substrate is also discussed.

Boson peak in overdoped manganites La1−xCaxMnO3

In the charge-ordered phase of strongly doped manganites La

Optical signatures of the superconducting Goldstone mode in granular aluminum: Experiments and theory

_{1-x}

Terahertz conductivity ofSr1−xCaxRuO3

Ca

Terahertz–infrared electrodynamics of overdoped manganites La1–xCaxMnO3

_x

Effects of oxygen plasma etching on Sb2Te3 explored by torque detected quantum oscillations

MnO

Field-theoretical basics on superconductivity

_3

Experimental studies on the Heavy Fermion metal CeCoIn 5

(