What is the point of boson sampling? - Thomas Brougham

Hello everyone,

This week's presenter is Thomas from Quantum Theory group. Please find details of the talk below:

Title: What is the point of boson sampling?
Time: 3pm on 30th August 2018
Venue: 257 Kelvin Building

Abstract:

In principle, quantum computers could provide an exponential speed-up on certain problems.  This would mean that problems which are currently intractable could be solved efficiently.  For example, one could quickly find the prime factors of extremely large numbers and thus crack RSA cryptography.

While this should work in principle, we don’t have any evidence that such exponential speed-ups would ever be possible in practice.  Realistic experimental situations could render this quantum advantage negligible for interesting problems.  It is for this reason that there is a great interest to show that an exponential quantum advantage can be realized in an experiment.  However, building a full quantum computer is rather difficult.  A simpler approach is to build an optical experiment that efficiently solves one single problem.  This is the idea behind boson sampling, which uses light within a passive linear optical network.   A full experimental demonstration of boson sampling would prove that quantum systems really can efficiently solve seemingly intractable problems.

Realizing a demonstration of boson sampling would be a great technical achievement.  However, the boson sampling problem is not very interesting in of itself.  In this talk I will argue that boson sampling could be used for other tasks.  For example, it can be used within cryptography and to help simulate the dynamics of certain quantum systems.  This would mean that while a boson sampler is not a full quantum computer, it could still have some applications.

See you all there!

Pavi.

Stuart Wilson on Computational imaging techniques in Micro-endoscopy

Hi all,

This week's talk will be presented by Stuart Wilson, a PhD student from the imaging concepts group. Stuart will be talking about his research on exploiting computational imaging methods to extend the depth-of-field and field-of-view in GRIN based micro-endoscopes. Details below:

Title: Advanced and Computational Imaging Techniques in Microendoscopy

Time and Venue: 3pm, Thu 9th Aug, 257 Kelvin Building

Abstract: The developing field of microendoscopy has the potential to overcome many of the risks associated with current approaches in clinical tissue characterisation and histology. These miniature optical devices enable deep tissue imaging at penetration depths of tens of millimetres – a technique known as optical biopsy – and can reduce the need for invasive surgical procedures. However, the miniaturisation of optical elements provides its own set of unique challenges, effectively degrading imaging performance by imposing a characteristically short depth of field, narrow field of view and a high affinity to optical aberrations. Using computational imaging techniques, we have demonstrated an order of magnitude increase in the depth of field, as well as a wider field of view and reduction in the intrinsic aberrations, resulting in a more robust optical probe for tissue characterisation.

See you all there!

Cheers,
Pavi.

Research in the Imaging concepts group

Hello everyone,

This week it is the Imaging Concepts Group's turn to give a peek into the research conducted in their labs. Andy, leader of the group, will present an overview of the research conducted mainly in the areas of computational imaging, multi-spectral imaging, infrared imaging, retinal imaging and in vivo imaging of rodents. Jonny will then takeover to tell us about the exciting research under his supervision on light-sheet microscopy and 3D imaging of a beating Zebrafish heart.

Link to the group's webpage: https://www.gla.ac.uk/schools/physics/research/groups/imagingconcepts/

See you all there!

Pavi.

Summary of weeks 2-4

Hi all,

It has been very interesting past few weeks with Vincenzo presenting his work on near zero refractive index materials on week 2 and Matt, Neal, Euan presenting the overview of the research conducted in the Optics group on weeks 3 and 4. Matt covered primary research interests of Miles, which included single pixel cameras, quantum gyroscope, imaging using entangled photon pairs for increased resolution and sub-shot noise imaging, optical trapping etc. Neal presented Sonia's research projects on Fresnel cones, talbot effect, vector beam shaping for STED type of microscopy and, trapping atoms and cooling them down to upto micro-Kelvin temperatures. Euan gave an overview of Johannes's research which focused primarily on building telescopic windows using lenslet-array pairs to build low-vision aids.

We had a steady attendance of over 40 in every talk and we hope to see similar attendance in future and looking forward to see many more interesting talks in the coming weeks.

Also, we have started sharing the presentations from our colloquia at:  https://www.slideshare.net/UOGOptics. The presentations on research groups' overview talks are currently being uploaded. Uploading presentations will be optional for the presenters so not all the presentations will be available, but we will try to make as many available as possible.

For now, some snapshots from the past few week.. Ciao Adios!

Week 4: Overview of The Optics Group continued...

Hello everyone,

I hope that you enjoyed Dr Matt Edgar's talk last week. To continue bringing you all up to speed with the research topics of the Optics group Dr Neal Radwell and Dr Euan Cowie will be talking about research areas which Matt only touched on last week.

Dr Neal Radwell

I'm a post-doctoral research associate in the Optics Group. I did my PhD at Strathclyde on the topic of 'Nonlinear Pattern Formation in Semi-conductor Lasers' and joined the Optics group in 2010. In those 8 years I have built the cold atom MOT and developed the dynamic SpOT and spatial EIT experiments with Sonja. I have worked with Miles to develop a single-pixel microscope and hybrid LiDAR system. The highlight of my more independent work is the Fresnel Cone research, where we show that simple glass cones can generate useful polarisation structures and we are developing technologies in polarimetry and microscopy based on Fresnel Cones. 

I'm going to be discussing the research from the 'Atoms Lab' lead by Sonja. The overarching research theme is 'Structured atom-light interactions' which covers topics from active and passive beam shaping, polarisation shaping, warm atomic vapour experiments, and culminating with out Cold Atom MOT in which we use structured light to spatially pattern atomic properties, which we hope will provide new understanding or methods for quantum memories.

Dr Euan Cowie

I’ve been a research associate in Optics since 2015.  I come from a background of nuclear and particle physics having attained my PhD in 2012 working in the Nuclear Physics Group here at Glasgow, before moving to the experimental Particle Physics group at the University of Bristol.  In both positions I worked on optical systems and sensors – specifically solid radiator Cherenkov detectors with ultra-fast Microchannel Plate PMTs. 

Upon joining the Optics group I dropped the sensors side of my work and focussed on the geometrical optics.  Here myself and Dr Johannes Courtial have been investigating novel structured optical systems, we call them pixelated optics, in which arrays of micro- or milli-metre sized telescopes are constructed into small Telescope Windows.  These can perform very general laws of refraction, allowing the construction of weird and wonderful purely-optical devices.  However my primary focus has been on using them as Low Vision Aids (LVAs), and it’s the development of this aspect I’ll go into detail on.

The talk will take place on Thursday 26th July at 3:00PM in Kelvin Room 257.

Snacks will be provided afterwards!
Kyle

Week 3: Overview of The Optics Group

Hello everyone!

This weeks talk will be given by Dr. Matt Edgar of the Optics group. Matt Edgar is a research associate in the Optics Group at the University of Glasgow. He received his BSc and PhD degrees in physics and astronomy in 2007 and 2011, respectively. He started his research career in the Institute for Gravitational Research at Glasgow, developing advanced interferometric techniques to enhance the sensitivity of long-baseline gravitational wave detectors. Since joining the Optics Group at Glasgow, he has been investigating the use of camera technology to perform fundamental tests of quantum mechanics and more recently has been developing computational imaging systems for applications in methane imaging and 3-D imaging.

In this talk Matt will provide a brief overview of the research activities within the Optics Group, highlighting a selection of recent experiments that cover a range of topics including Quantum Optics, Classical Optics, Computational Imaging, Atom Optics, Geometrical Optics as well as a selection of exciting outreach activities that he has been involved in over the years.

The talk will take place in Kelvin 257 on Thursday 19th July at 3:00PM.

See you there!
Kyle

Week 2: Vincenzo Bruno on ENZ materials

Hi all,

This week's talk will be given by Vincenzo Bruno, one of the PhD students in our group.

Epsilon-near-zero material as a platform for strong light-matter interaction.

Epsilon-near-zero (ENZ) materials, both artificial and engineered, have attracted an increasing interest due to the peculiar way how light interacts with such materials. The ENZ range, where the real part of the permittivity (ε) approaches or crosses the zero, can be obtained in different systems, including metal dielectric composite or highly doped semiconductor. A particular family of natural ENZ materials is the Transparent conductive oxide (TCO), as Indium Tin Oxide (ITO) and Aluminum doped Zinc Oxide (AZO). Due to the low optical losses in the ENZ region, these materials present a near zero index of refraction in the same spectral range. As the effective wavelength in such material tend to infinity as n → 0 in the ENZ region, a thick film of TCO could behave essentially as the deeply subwavelength thin film. Was recently proved that, in an AZO film, this near-zero response leads to an enhancement of the non-linear response in terms of optical Kerr effect with a relative change of Δn over 400% in a ultrafast temporal window. These features, together, make the AZO a suitable platform for the study of fundamental physical problems in time dependent materials, overcoming the usually weak light-matter interaction.

Same time, different room (hopefully it will be a little less cramped): 3pm Thurs 12th July, Kelvin 257.

Cheers,
Ash