Friday, 2 September 2016

Who needs a single glass material ?

Hollow optical fibres based on antiresonance can be made with different materials at the core boundary!!! The antiresonance mechanism takes please anyway, in a comparable way to what happens in a conventional hollow antiresonant fiber !!! This apply to fibers covered with semiconductor (white lines in the left picture) but it would  apply also to more complex structures.
Overall all of these structures can be thought like equivalent to a single material fibre with the right thickness and refractive index.
I will present these results soon in Rochester (USA) at the Frontiers in Optics Conference. Link

Tuesday, 8 March 2016

Visiting Professor in Italy

From the 7th to the 11th of March I am a visiting professor at the University of Pavia in Italy. I am giving some lessons to Italian students, postgraduates and researchers about Microstructured Optical Fibers, Novel type of optical Fibers (Multimaterial, Semiconductor fibres and others) and naturally hollow core optical fibers (including antiresonant fibers). It is a great pleasure to be back at the University where I firstly got to know what is an optical fibre and a laser!

Tuesday, 10 November 2015

Novel hollow fibers for novel lasers

While I was working in Bath last year, I gave a major fundamental contribution to the redaction of a research proposal to the Engineering and Physical Research Council, concerning the development of novel hollow core antiresonant fibers and their use in combination with ultraviolet lasers. The project proposal, which is a collaboration between the University of Bath, Heriot-Watt University, M-Solv Ltd, Litron Lasers, Powerlase Photonics Ltd and Choerent Scotland,  was submitted shortly after I left Bath and it has now been granted more than 700 000 GBP to the University of Bath and Heriot-Watt University. The title I have chosen for this 3 years project follows the style of my previous 2 publications in the subject: “Hollow antiresonant fibres for visible and ultraviolet beam delivery”.

Thursday, 3 September 2015

Who needs ultrapure glass ?

The birth of optical fibers as an optical communication channel goes along with the development of ultrapure glass. In the late 60ths scientists like Charles Kao had envisaged that optical fibers made of ultrapure glass could have been produced and properly designed to allow the transmission of data over long distances. Fiber material properties set today the lowest attenuation boundary of standard optical fibers. However today hollow core antiresonant fibers can allow a glass overlap of the optical power travelling in the optical fiber of less than 0.01% !! Then why shall we use ultrapure silica glass in order to transmit data at the highest possible speed (low latency) within a hollow core optical fiber?  Do we really need silica glass? Can we (in principle) achieve even better optical guidance in a hollow core fiber by using a different type of glass? Maybe that glass will be cheaper, broadly available and easier to manufacture? Maybe it will be also easier to use in combination with other standard optical technologies?

In this famous movie a scientist (Christopher Lloyd) builds a “time machine” which is operated by the nuclear energy generated by Plutonium. However, after travelling to the future (30 years), he finds out that this machine can be simply powered by using garbage! What about finding out that the optical fibres of the future will be made by the glass we commonly find in the dustbin of our house?

Friday, 22 May 2015

Flexibility is better

Novel hollow core optical fibers are not based anymore on the conceptual rigidity of its ancestors: not only a periodicity is not required, but also the size and shape of the anti-resonant elements within the fibre structure can be modified. This new flexibility can open the way to new and exciting optical properties: hollow fibres with very wide transmission bandwidth, with very high birefringence, with controlled modal shape, with controlled dispersion, with ultra-low attenuation, with enhanced gas sensing properties and so on. Opposed to structural rigidity, the design flexibility of these new optical fibers appears to be the key to access novel or better use of this fibre technology.