Quantum noise reduction using a cavity with a Bose Einstein condensate

We study an optomechanical system in which the collective density excitations (Bogoliubov modes) of a Bose Einstein condensate (BEC) is coupled to a cavity field. We show that the optical force changes the frequency and the damping constant of the collective density excitations of the BEC. We further analyze the occurrence of normal mode splitting (NMS) due to mixing of the fluctuations of the cavity field and the fluctuations of the condensate with finite atomic two-body interaction. The NMS is found to vanish for small values of the two-body interaction. We further show that the density excitations of the condensate can be used to squeeze the output quantum fluctuations of the light beam. This system may serve as an optomechanical control of quantum fluctuations using a Bose Einstein condensate.Comment: 8 figure

Barriers and motivations affecting information systems usage by Hajj-Umrah religious tourism operators in Saudi Arabia

Hajj & Umrah religious tourism accounts for seven million visitors each year in Saudi Arabia. The government has recently taken initiatives to promote the use of Information Systems (IS) in the religious tourism industry, encouraging firms to adopt IS innovations like e-commerce and enforcing the use of the Makha'a information system in Umrah for external pilgrims and the Yosr information system in Hajj for internal pilgrims. This study outlines the motivations and challenges that affect the utilisation of various IS services in the Saudi religious tourism industry through a qualitative analysis of the views and perceptions of senior executives and owners of travel firms. The findings suggest that while government initiatives and industry competitiveness were two positive factors promoting IS use, there are some major barriers preventing private firms from fully utilising the advantages of information systems. These include external factors such as lack of support from the IT industry and access to IT resources as well as internal factors within an organisation such as lack of commitment or the need for professional IT expertise. The study finds that relative advantage is a critical contributor to IS utilisation which depends on information systems characteristic

A social network analysis of the co-authorship network of the Australasian Conference of Information Systems from 1990 to 2006

Using bibliographic data extracted from an Endnote database, social network analysis techniques were used to generate and analyse a network of co-authors with the aim of developing an understanding of the research community that produces the research knowledge published by the Australasian Conference on Information Systems (ACIS). The ACIS community was found to be a healthy small-world community that kept evolving in order to provide an environment that supports collaboration and sharing of ideas between researchers. It was also found that, unlike a similar analysis of the European Conference (ECIS), the Australasian scene was not dominated by a couple of key researchers as quite a significant number of popular researchers were identified

A customer relationship management case study : critical success factors in action

Critical success factors (CSFs) are seen as a way of identifying those elements of an information systems project that are critical for the success of that project. However, existing research about CSFs has been largely derivative in nature. Many researchers use the existing literature to derive their lists of CSFs for industries, IS domains (such as: EIS, ERP, CRM) and case studies. Moreover, these lists have come from only one targeted group of people, senior management. There is a need for a new perspective and fresh primary sources. This paper argues that after 27 years of CSF method application little theoretical development has occurred Firstly, CSFs are not easily deciphered or compiled; and secondly, hierarchical (multiple) lists of CSFs may present a better representation of the position. Using a case study in CRM adoption and implementation, this paper discusses research undertaken to determine the nature of CSFs and highlights the issues, and problems in CSFs thinking over the past two decades, while providing a new interpretation of CSFs in use

Measurement of radiation-pressure-induced optomechanical dynamics in a suspended Fabry-Perot cavity

We report on experimental observation of radiation-pressure induced effects in a high-power optical cavity. These effects play an important role in next generation gravitational wave (GW) detectors, as well as in quantum non-demolition (QND) interferometers. We measure the properties of an optical spring, created by coupling of an intense laser field to the pendulum mode of a suspended mirror; and also the parametric instability (PI) that arises from the nonlinear coupling between acoustic modes of the cavity mirrors and the cavity optical mode. Specifically, we measure an optical rigidity of $K = 3 \times 10^4$ N/m, and PI value $R = 3$.Comment: 4 pages, 3 figure

A squeezed state source using radiation pressure induced rigidity

We propose an experiment to extract ponderomotive squeezing from an interferometer with high circulating power and low mass mirrors. In this interferometer, optical resonances of the arm cavities are detuned from the laser frequency, creating a mechanical rigidity that dramatically suppresses displacement noise. After taking into account imperfection of optical elements, laser noise, and other technical noise consistent with existing laser and optical technologies and typical laboratory environments, we expect the output light from the interferometer to have measurable squeezing of ~5 dB, with a frequency-independent squeeze angle for frequencies below 1 kHz. This squeeze source is well suited for injection into a gravitational-wave interferometer, leading to improved sensitivity from reduction in the quantum noise. Furthermore, this design provides an experimental test of quantum-limited radiation pressure effects, which have not previously been tested.Comment: 15 pages, 6 figures, submitted to Phys. Rev.

Squeezing in the audio gravitational wave detection band

We demonstrate the generation of broad-band continuous-wave optical squeezing down to 200Hz using a below threshold optical parametric oscillator (OPO). The squeezed state phase was controlled using a noise locking technique. We show that low frequency noise sources, such as seed noise, pump noise and detuning fluctuations, present in optical parametric amplifiers have negligible effect on squeezing produced by a below threshold OPO. This low frequency squeezing is ideal for improving the sensitivity of audio frequency measuring devices such as gravitational wave detectors.Comment: 5 pages, 6 figure

Achieving ground state and enhancing entanglement by recovering information

For cavity-assisted optomechanical cooling experiments, it has been shown in the literature that the cavity bandwidth needs to be smaller than the mechanical frequency in order to achieve the quantum ground state of the mechanical oscillator, which is the so-called resolved-sideband or good-cavity limit. We provide a new but physically equivalent insight into the origin of such a limit: that is information loss due to a finite cavity bandwidth. With an optimal feedback control to recover those information, we can surpass the resolved-sideband limit and achieve the quantum ground state. Interestingly, recovering those information can also significantly enhance the optomechanical entanglement. Especially when the environmental temperature is high, the entanglement will either exist or vanish critically depending on whether information is recovered or not, which is a vivid example of a quantum eraser.Comment: 9 figures, 18 page

E-readiness to G-readiness: developing a green information technology readiness framework

Businesses are under increasing pressure from competitors, regulators and community groups to implement sustainable business practices. Balancing economic and environmental performance to be green and competitive is therefore a key strategic issue. The increased discussion on green information technology (IT) has sparked the interest of this research. Green IT is poised to influence not only technology but also competitive strategy and even the legality of some business strategic options. Understanding and leveraging Green IT is therefore critical for businesses¿ continued progress. Nevertheless, the principles, practices and value of Green IT is yet to be researched. This paper introduces the concept of Green IT and describes the main pillars of a g-readiness framework to help organisations evaluate their readiness for adopting Green IT. It argues that just as e-readiness has been, and continues to be, a critical quality in the digital economy, g-readiness is an equally critical quality in the low carbon digital economy. Without a clear understanding of g-readiness, organisations would approach Green IT initiatives on an ad hoc and somewhat reactive basis which is undesirable