27/08/2018

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.

08/08/2018

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.