With the aim of making optics reachable to all audiences, regardless of their age or area of study, we have decided to select, build and test a set of four experiments based on optical phenomena. An important factor in our approach is that the experiments should be used by any non-experienced exhibitor to amaze the audience and to arise in them interest in optics. Ease of setup is therefore desired. Requirements such as durability, repeatability and reduced cost are welcome as well. Taking advantage of the low prices of laser pointers, we focused on experiments which use this nowadays accessible element. The experiments that integrate our selection, costing less than USD75, are: a water stream optical fiber, curved light beams on a honey-water mixture, an optical music transmitter-receiver, and holographic film projections. Among the covered concepts are reflection and refraction of light, color, optical communications, optical interference and modern everyday life’s applications. We have presented these setups in activities at our university to a wide range of educational levels, from 12-year old students, passing by last year high school students on a career day event, not leaving behind undergraduate students of any discipline. Moved by the positive response of the audience, we plan to expand its application to continuing education courses and kids’ science fairs. We proved that having low-cost setups, useful when teaching science in developing countries, can help to broaden the target audience.
In 1964, J. Bell introduced an inequality that stated a mathematical bound for any physical system that holds both locality and realism; if we violate this inequality, it is clear that we have to reconsider the previous statement. In our work, we report an experimental activity with photons suitable for undergraduate students that makes them question these naïve ideas of nature’s behavior. With a pre-aligned setup, our students tested and violated Bell’s inequality in a two-hour laboratory session, using two distant photons entangled in polarization. In addition, complementing an educational approach to this phenomenon, the usually called S function, that quantifies correlations, was mapped using different detection angles in one of the two locations. In particular, a more complete picture of the S function, allow us to identify the initial state of light. We show in this work that it is possible for undergraduate students to question some of our common sense ideas of nature using experiments with photons.
A project to introduce secondary school students to statistical physics and biophotonics by means of an optical tweezers is presented. Interestingly, the project is completely experimental and no advanced calculus or physics knowledge is necessary. The project starts from the construction of the optical tweezers itself and therefore is also useful to introduce basic concepts of optics.
Photonics is an upcoming field that offers immense possibilities in frontier science, technology, and industry. The topic needs to be introduced among the young students to motivate their interest and passion for light. However, the potential of optics and photonics as a very exciting part of science is not always fully explored in high school education. With the motivation to contribute an initiative along these lines, a two-hour program was developed and successfully implemented at ICFO-The institute of photonics sciences. Further recent efforts were directed towards the improvement of this program which resulted in the advanced version. This improved version focuses on explaining the ray and wave nature of light, as well as the demonstration of the conservation of energy in relation to optics. The event was organized and the demonstrations were carried out by ICFO PhD students enrolled in the ICFO Optical Society of America (OSA) and SPIE student chapters.
One of the goals of quantum optics is to implement new sources of quantum light with tunable control of the
relevant photonic properties. Here, we add to the toolkit of available techniques in quantum optics for the full
control of the properties of quantum light, new strategies to manage the spectrum of photons, namely, type
of frequency correlations, bandwidth and waveform. As a source of quantum light, spontaneous parametric
downconversion (SPDC) is considered. Interestingly, the techniques presented might be used in any nonlinear
medium and frequency band of interest. One of the schemes to control the frequency correlations makes use of
light pulses with pulse-front tilt. The method is based on the proper tailoring of the group velocities of all the
waves that interact in the nonlinear process, through the use of beams with angular dispersion. Noncollinear
SPDC is the other strategy that is considered, since it allows mapping the spatial characteristics of the pump
beam into the frequency properties of the downconverted photons.
The bandwidth and the frequency correlations of quantum light can be considered as a resource for the implementation of new quantum information algorithms, and it should enable the applicability of quantum techniques not yet implemented. For that purpose, the control of the frequency correlations, and the bandwidth, of single and paired photons is an essential ingredient, since the optimum bandwidth, as well as the most appropriate type of frequency correlations for a specific quantum application, depend on the specific quantum information application under consideration. Here we elucidate and implement new strategies to tailor the frequency properties of quantum light. Such strategies, which are based on the use of non collinear spontaneous parametric down conversion (SPDC) configurations, include the generation of narrow and enhanced bandwidth quantum light, the control of the frequency correlations of paired photon, and the generation of heralded single photons with a high degree of purity from pairs of uncorrelated photons.