7 research outputs found
Raising and lowering operators, factorization and differential/difference operators of hypergeometric type
Starting from Rodrigues formula we present a general construction of raising
and lowering operators for orthogonal polynomials of continuous and discrete
variable on uniform lattice. In order to have these operators mutually adjoint
we introduce orthonormal functions with respect to the scalar product of unit
weight. Using the Infeld-Hull factorization method, we generate from the
raising and lowering operators the second order self-adjoint
differential/difference operator of hypergeometric type.Comment: LaTeX, 24 pages, iopart style (late submission
Generally Deformed Oscillator, Isospectral Oscillator System and Hermitian Phase Operator
The generally deformed oscillator (GDO) and its multiphoton realization as
well as the coherent and squeezed vacuum states are studied. We discuss, in
particular, the GDO depending on a complex parameter q (therefore we call it
q-GDO) together with the finite dimensional cyclic representations. As a
realistic physical system of GDO the isospectral oscillator system is studied
and it is found that its coherent and squeezed vacuum states are closely
related to those of the oscillator. It is pointed out that starting from the
q-GDO with q root of unity one can define the hermitian phase operators in
quantum optics consistently and algebraically. The new creation and
annihilation operators of the Pegg-Barnett type phase operator theory are
defined by using the cyclic representations and these operators degenerate to
those of the ordinary oscillator in the classical limit q->1.Comment: 21 pages, latex, no figure
Photoconductivity and photovoltaic effect in indium selenide
Transport and phototransport properties of crystalline indium monoselenide (InSe) doped with a variety of elements are reported. Measured mobilities, lifetimes, and effective diffusion lengths of photoexcited carriers are used to interpret electrical and photovoltaic properties of several different structures. These include p‐n junctions, bismuth/p‐type InSe, platinum/n‐type InSe, and indium tin oxyde (ITO)/p‐type InSe. External solar efficiencies of the best devices are between 5% and 6%. The influence on the efficiency of the various parameters is evaluated, and ways of improvement are discussed