29 citations · 104 across the 10 of their papers we have counts for
10 papers
Orthogonality catastrophe in a composite fermion liquid
Darren J. T. Leonard, T. Portengen, V. Nikos Nicopoulos +1
We discuss the emergence of an orthogonality catastrophe in the response of a composite fermion liquid as the filling factor νapproaches 1/2m, where m=1,2,3.... A tunneling experim…
Acoustic attenuation in a type-II superconductor at high magnetic fields
G. M. Bruun, V. N. Nicopoulos, N. F. Johnson
We have calculated the longitudinal acoustic attenuation in a type-II superconductor in high magnetic fields within a mean-field BCS theory. We predict two new features in the corr…
Optics with Quantum Hall Skyrmions
T. Portengen, J. R. Chapman, V. Nikos Nicopoulos +1
A novel type of charged excitation, known as a Skyrmion, has recently been discovered in quantum Hall systems with filling factor near ν= 1. A Skyrmion -- which can be thought of a…
Skyrmionic excitons
T. Portengen, J. R. Chapman, V. Nikos Nicopoulos +1
We investigate the properties of a Skyrmionic exciton consisting of a negatively charged Skyrmion bound to a mobile valence hole. A variational wave function is constructed which h…
Validity of the Gor'kov expansion near the upper critical field in type II superconductors
G. M. Bruun, V. N. Nicopoulos
We have examined the validity of the Gor'kov expansion in the strength of the order parameter of type II superconductors near the upper critical field. Although the degeneracy of t…
Photoluminescence signature of skyrmions at ν= 1
T. Portengen, J. R. Chapman, V. Nikos Nicopoulos +1
The photoluminescence spectrum of quantized Hall states near filling factor ν= 1 is investigated theoretically. For ν>= 1 the spectrum consists of a right-circularly polarized (RCP…
Stability of optically-active charged excitons in quasi-two dimensional systems
James R. Chapman, Neil F. Johnson, V. Nikos Nicopoulos
A negatively charged quasi-two dimensional exciton () is solved exactly numerically in the presence of a uniform perpendicular B-field. Various quasi-two dimensional geometrie…
Ginzburg-Landau-Gor'kov Theory of Magnetic oscillations in a type-II 2-dimensional Superconductor
G. M. Bruun, V. N. Nicopoulos, N. F. Johnson
We investigate de Haas-van Alphen (dHvA) oscillations in the mixed state of a type-II two-dimensional superconductor within a self-consistent Gor'kov perturbation scheme. Assuming…
Optical properties of a two-dimensional electron gas at even-denominator filling fractions
Darren J. T. Leonard, Neil F. Johnson, V. Nikos Nicopoulos +1
The optical properties of an electron gas in a magnetic field at filling fractions ν= {1\over 2m} (m=1,2,3...) are investigated using the composite fermion picture. The response of…
Evolution of Magnetic Properties of Lightly Doped Copper Oxides
L. P. Gor'kov, V. Nikos Nicopoulos, Pradeep Kumar
We study how doping destroys the AF order in the layered cuprates within the framework of the charge--transfer insulator concept. We use the criterion of stability of the AF backgr…