Complexity of Polarized Spatial Patterns in Large Area Square VCSEL

We consider pattern selection process in a wide aperture VCSEL near threshold. We show that for a square geometry of the laser aperture, the patterns formed at lasing threshold can be very complicated because of a possible misalignment between directions of an intrinsic spatial anisotropy of VCSEL and lateral boundaries of its aperture. The analogy with quantum billiard structures is established, and fingerprints of wave chaos are found. Influence of localized inhomogeneous in the pump current is also considered.Comment: 10 pages, 8 figures, uses REVTEX

Bistability conditions between lasing and non-lasing states for vertical-cavity surface-emitting lasers with frequency-selective optical feedback

This paper gives analytical treatment and experimental details on on/off-bistability in vertical-cavity surface-emitting lasers with frequency-selective feedback by a grating. In particular, the conditions for the coexistence of lasing and nonlasing states and an abrupt turn-on behaviour at threshold are derived using an envelope approximation. The theoretical and experimental results are in satisfactory agreement

Alien Registration- Loiko, Maciez (Augusta, Kennebec County)

https://digitalmaine.com/alien_docs/18716/thumbnail.jp

Free Space Optical Polarization De-multiplexing and Multiplexing by means of Conical Refraction

Polarization de-multiplexing and multiplexing by means of conical refraction is proposed to increase the channel capacity for free space optical communication applications. The proposed technique is based on the forward-backward optical transform occurring when a light beam propagates consecutively along the optic axes of two identical biaxial crystals with opposite orientations of their conical refraction characteristic vectors. We present experimental proof of usefulness of the conical refraction de-multiplexing and multiplexing technique by increasing in one order of magnitude the channel capacity at optical frequencies in a propagation distance of 4m

Innovative potential of the consumer sector of the economy: financial, economic and legal aspects

The authors of the article have analyzed the legal, financial and economic aspects of the innovative capacity of the consumer sector of the national economy of Ukraine. The problems that slow down the process of forming the innovative capacity of the consumer sector of the national economy have been identified. The results of theoretical and methodological research of the essence of the innovative capacity of the consumer sector of the national economy have been presented. It has been offered to consider the following the most influential financial and economic aspects for the formation of the innovative capacity of the consumer sector of the national economy: the dynamics of issuing security documents for industrial property facilities in Ukraine; volumes and sources of financing of innovation activity in Ukraine; motivation to intensify innovation activity. It has been concluded that Ukraine has created a regulatory legal base for regulating innovation activity, but it needs further improvement and adaptation to European legislation. It has been determined that the innovative capacity of education as a component of the consumer sector of the national economy is influenced by several factors, namely: the dynamics of budget funding of general secondary educational institutions and the dynamics of changing in the number of such institutions. The authors have suggested the list of resources, which are expedient to involve at acceleration of the process of the formation of innovative capacity of the consumer sector of the national economy

Электронное учебное пособие по учебной дисциплине "Философия" обязательного модуля "Философия" для студентов 1 ступени высшего образования всех специальностей очной и заочной форм получения образования

The textbook includes materials of a lecture course, guidelines for independent study of the discipline "Philosophy" a list of additional literature for independent, scientific and research work of students

Coherent injecting, extracting, and velocity filtering of neutral atoms in a ring trap via spatial adiabatic passage

We introduce here a coherent technique to inject, extract, and velocity filter neutral atoms in a ring trap coupled via tunneling to two additional waveguides. By adiabatically following the transverse spatial dark state, the proposed technique allows for an efficient and robust velocity dependent atomic population transfer between the ring and the input/output waveguides. We have derived explicit conditions for the spatial adiabatic passage that depend on the atomic velocity along the input waveguide as well as on the initial population distribution among the transverse vibrational states. The validity of our proposal has been checked by numerical integration of the corresponding two dimensional Schr\"odinger equation with state-of-the-art parameter values for $^{87}$Rb atoms and an optical dipole ring trap.Comment: To be published in European Physical Journal