828 citations · 1.7k across the 38 of their papers we have counts for
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Phonon Anomalies, Orbital-Ordering and Electronic Raman Scattering in iron-pnictide Ca(Fe0.97Co0.03)2As2: Temperature-dependent Raman Study
Pradeep Kumar, D. V. S. Muthu, L. Harnagea +3
We report inelastic light scattering studies on Ca(Fe0.97Co0.03)2As2 in a wide spectral range of 120-5200 cm-1 from 5K to 300K, covering the tetragonal to orthorhombic structural t…
Superconducting Fluctuations and Anomalous Phonon Renormalization much above superconducting transition temperature in Ca4Al2O5.7Fe2As2
Pradeep Kumar, A. Bera, D. V. S. Muthu +3
Raman studies on Ca4Al2O5.7Fe2As2 superconductor in the temperature range of 5 K to 300 K, covering the superconducting transition temperature Tc ~ 28.3 K, reveal that the Raman mo…
Temperature-dependent Raman study of CeFeAsO0.9F0.1 Superconductor: Crystal field excitations, phonons and their coupling
Pradeep Kumar, Anil Kumar, Surajit Saha +5
We report temperature-dependent Raman spectra of CeFeAsO0.9F0.1 from 4 K to 300 K in spectral range of 60 to 1800 cm-1 and interpret them using estimates of phonon frequencies obta…
Raman Evidence for Superconducting Gap and Spin-Phonon Coupling in Superconductor Ca(Fe0.95Co0.05)2As2
Pradeep Kumar, Achintya Bera, D. V. S. Muthu +8
Inelastic light scattering studies on single crystal of electron-doped Ca(Fe0.95Co0.05)2As2 superconductor, covering the tetragonal to orthorhombic structural transition as well as…
Anomalous Raman scattering from phonons and electrons of superconducting FeSe
Pradeep Kumar, Anil Kumar, Surajit Saha +6
We report interesting anomalies in the temperature dependent Raman spectra of FeSe measured from 3K to 300K in the spectral range from 60 to 1800 cm and determine t…
Theory of a Higher Order Phase Transition: Superconducting Transition in BKBO
P. Kumar
We describe here the properties expected of a higher (with emphasis on the order fourth) order phase transition. The order is identified in the sense first noted by Ehrenfest, name…
Thermodynamics of a Higher Order Phase Transition: Scaling Exponents and Scaling Laws
P. Kumar, A. Saxena
The well known scaling laws relating critical exponents in a second order phase transition have been generalized to the case of an arbitrarily higher order phase transition. In a h…
Clapping modes in unconventional superconductors
A. V. Balatsky, P. Kumar, J. R. Schrieffer
We consider a superconducting state with a mixed symmetry order parameter components, e.g. or with . We argue for the existence of the new orbital magnet…
Magnetization Measurements on Single Crystals of Superconducting Ba0.6K0.4BiO3
Donavan Hall, R. G. Goodrich, C. Grenier +3
Extensive measurements of the magnetization of superconducting single crystal samples of Ba0.6K0.4BiO3} have been made using SQUID and cantilever force magnetometry at temperatures…
Thermodynamics of the Superconducting Phase Transition in Ba_{0.6}K_{0.4}BiO_3
P. Kumar, Donavan Hall, R. G. Goodrich
We suggest that the transition to superconductivity in a single crystal of Ba_{0.6}K_{0.4}BiO_3 with a T_c = 32K, and having critical fields with anomalous temperature dependencies…
Properties of Phase transitions of a Higher Order
Pradeep Kumar
The following is a thermodynamic analysis of a III order (and some aspects of a IV order) phase transition. Such a transition can occur in a superconductor if the normal state is a…