摘要:

A lack of symmetry in the intensities of the plus and minus diffraction orders in the output Fourier plane of a liquid-crystal light valve has been observed. Measurement results and an intuitive discussion of this effect are presented.

ISSN:0950-0340    

DOI:10.1080/09500348714551251

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/09500348714551261

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/09500348714551281

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/09500348714551301

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

ISSN:0950-0340    

DOI:10.1080/09500348714551311

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

In 1955 Pancharatnam showed that a cyclic change in the state of polarization of light is accompanied by a phase shift determined by the geometry of the cycle as represented on the Poincaré sphere. The phase owes its existence to the non-transitivity of Pancharatnam's connection between different states of polarization. Using the algebra of spinors and 2 × 2 Hermitian matrices, the precise relation is established between Pancharatnam's phase and the recently discovered phase change for slowly cycled quantum systems. The polarization phase is an optical analogue of the Aharonov-Bohm effect. For slow changes of polarization, the connection leading to the phase is derived from Maxwell's equations for a twisted dielectric. Pancharatnam's phase is contrasted with the phase change of circularly polarized light whose direction is cycled (e.g. when guided in a coiled optical fibre).

ISSN:0950-0340    

DOI:10.1080/09500348714551321

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The photoexcitation of a structured continuum of states from a single ground state is considered. We investigate an analytically soluble model in which the dipole matrix elements between the ground state and the continuum vary sinusoidally between zero and a maximum. The time-evolution of the ground-state population still exhibits the periodic disruption observed in the Bixon-Jortner model, although the disruption is much reduced. We allow the ground state to be resonant with an arbitrary place in the continuum; population trapping is observed in the case of resonance with a zero in the continuum. We compare and contrast the results obtained with this model with those of quasi-continuum excitation. Lastly, we examine the final-state spectrum.

ISSN:0950-0340    

DOI:10.1080/09500348714551331

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The dynamical properties of a two-level atom interacting with a single non-decaying mode of an electromagnetic field in a binomial state are studied. The statistical aspects of the field, such as intensity-intensity correlation and squeezing, are also investigated. The binomial state reduces to a pure number state and a pure coherent state in different limits. Hence it enables us to study how the sinusoidal Rabi oscillations in a pure number state develop to give rise to the phenomenon of collapse and revival which has been studied extensively in the coherent-state field. In addition, the binomial state exhibits squeezing for certain values of parameters, but it is not a minimum-uncertainty-product state.

ISSN:0950-0340    

DOI:10.1080/09500348714551341

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A rigorous approach for solving a large class of scattering problems is presented and implemented for the classical problem of scattering by a perfectly conducting circular cylinder. This method is characterized by the preliminary calculations of a ψ distribution, deduced from a new kind of boundary value problem. This ψ distribution allows us to express the surface current density in the form of the integral of a known function, valid for any kind of incident wave. Numerical comparisons with the classical method are performed. A numerical study of ψ allows us to deal with cylinders having diameters larger than 100 wavelengths on a HP 1000 F minicomputer.

ISSN:0950-0340    

DOI:10.1080/09500348714551351

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A cylindrical birefringent fibre orientated diagonally between two crossed polarizers can be regarded as a single-, double- or multiple-slit source of light, depending on the refractive index of the medium which surrounds the fibre. When normally trans-illuminated by monochromatic light and observed through a polarizing microscope fitted with a condenser-slit diaphragm, the fibre produces specific interference patterns in the exit pupil of the microscope objective. These patterns manifest themselves as optical Fourier transforms. Their properties and possible applications are discussed. The experiments were performed using polymeric textile fibres.

ISSN:0950-0340    

DOI:10.1080/09500348714551361

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor