Optics for the Cloud lecture series

Optics for the Cloud lecture series

Upcoming speakers

Advanced polarized light microscopy for mapping molecular orientation

headshot of Prof Rudolf Oldenbourg

Prof Rudolf Oldenbourg, Senior Scientist
Marine Biological Laboratory, MA

Tuesday, 24 September 2019
09:30–11:00 | Followed by refreshments

Abstract

Polarization is a basic property of light, but the human eye is not sensitive to it. Therefore, we don’t have an intuitive understanding of polarization-dependent phenomena. However, polarized light plays an important role in nature, and polarization microscopy can be used to understand molecular order in living cells, tissues, and whole organisms. The talk will describe a polarized light microscope, developed at the Marine Biological Laboratory (MBL) in Massachusetts, called the LC-PolScope. This instrument measures the orientation of molecules at every resolved specimen point simultaneously. In addition to birefringence and diattenuation, it can also map the polarized fluorescence of fluorophores used to label structures like cell membranes and filaments. Recently, these techniques have been extended to multi-view microscopes. With a single-view microscope, measuring the inclination angles of the optical axes of bonds, particles, and fluorophores with respect to the focal plane remains a challenge. Multi-view microscopes record images along several viewing directions, thereby enabling unambiguous measurement of the three-dimensional orientation of molecules and their aggregates.

Biography

Rudolf Oldenbourg is a Senior Scientist at the MBL. He was born in Munich, from whose Technical University he graduated in 1976. He received a Max Planck Fellowship for graduate work in Grenoble, and a PhD in physics in 1981 from the University of Konstanz. In 1984, Oldenbourg joined the faculty at Brandeis University in the US, and in 1989 he transferred to the MBL to begin a collaboration with Shinya Inoué which led to important advances in polarized light microscopy techniques for studying living cells.


Past speakers

Antennas for light and their applications in classical optics

headshot of Dr Rupert Oulton

Dr. Rupert Oulton, Reader in Physics
Imperial College London

Thursday, 18 July 2019
16:00–17:30 | Followed by refreshments

Abstract

Gold particles with dimensions of about a hundred nanometres are resonant at visible wavelengths and thus serve as antennas for light. Over the past two decades, nanofabrication technology has advanced to the point where a wide range of applications for optical antennas are now possible. Individually, they may be exploited for sensing at the sensitivity of single molecules. Within arrays, they can be deployed to realise thin and planar optical elements, such as lenses and polarisers.

The talk will address some contemporary themes in this diverse field, and their applications in classical optics. Each example highlights a key advantage of optical antennas: for example, using their nanometric scale to quantify lens aberration, or using their tightly focussed optical field to realise strong nonlinear optical effects for optical pulse characterisation. The talk will also cover Rupert’s work on hot electrons: remarkably, electrons excited by light in metals can be over 1000°C hotter than their surroundings! This could enable new and potentially inexpensive infrared detectors.

Biography

Rupert Oulton is Reader in Physics at Imperial College London. He graduated with a PhD in Physics from Imperial on optoelectronic microcavity devices and went on to research plasmonics and metamaterials at the University of California at Berkeley, in particular nano-lasers. He returned to the UK and Imperial as an EPSRC Fellow and Leverhulme Lecturer in 2010. His current research interests include the linear and nonlinear optics of metallic nanostructures, nanoscale lasers and quantum optics.


Photons in the cloud: communicating and storing data

headshot of John Marsh

John Marsh, Professor of Optoelectronic Systems
University of Glasgow

Thursday, 13 June 2019
16:00–17:30 | Followed by refreshments

Abstract

Photons underpin our lives, from our ability to see through to our communication systems. While computers are built around electronics, long-haul communications are built around light. Photonic integrated circuits (PICs) are the optoelectronic equivalent of the silicon chips that have revolutionised society over the last 70 years. PIC devices such as lasers, modulators, waveguides, and detectors are widely used in communications, sensing, healthcare and quantum technology. Optical communications represent almost 60% of this market, with PICs currently deployed mainly in the long-haul network. However, because of society’s ever-increasing demands for data, they are migrating rapidly into the office and home.

PICs are also key to the next generation of magnetic disk drive technology for use in the cloud. Currently, no other storage technology can meet the cost/performance criteria, but new approaches are needed to increase the storage density. Heat-assisted magnetic recording (HAMR) involves local heating of magnetic media so data can be written at densities above 1 Tbit/in2. By integrating lasers, waveguides and plasmonic antennas, PICs focus enough energy on the disk to raise the local temperature to up to 500 °C within 1 ns. The market for HAMR is expected to be billions of units per annum, a truly exciting volume application for PIC technology.

Biography

John Marsh studied Engineering and Electrical Sciences at Cambridge before pursuing a PhD in compound semiconductors at the University of Sheffield.  He moved to the School of Engineering at Glasgow in 1986 where he was appointed Professor in 1996. He is a Fellow of the Royal Academy of Engineering, Royal Society of Edinburgh and IEEE.


Structured light: seeing less to see more in optical microscopy

Mark NeilMark Neil, Professor of Photonics
Imperial College London

Monday, 18 March 2019
16:00–17:15 | Followed by refreshments

Abstract

Optical microscopy techniques can be greatly enhanced from simply imaging what you see in the focus of a microscope objective by structuring the light that you use to illuminate the object. The classic example of this is the confocal microscope where a point illumination is used with a point detector to reject light that comes from outside the focal plane. That technique enables high-contrast, three-dimensional imaging of an object, and can even achieve an improvement in resolution. This talk covers a range of techniques, some wide-field, and some point scanning, but all loosely based on the confocal principle, that can achieve or even better the performance of the classic confocal microscope. While the confocal microscope most benefitted from the invention of the laser, we show how it is developments in optical components, detector technology and computational power that are enabling more recent developments, and opening up new possibilities for applications such as optical data storage.

Biography

Mark Neil studied Natural Sciences at Cambridge before pursuing his PhD in optical information processing at the Engineering Department there. Moving to the Department of Engineering Science at Oxford University he continued his work in optics as a post-doctoral researcher and college lecturer, before joining the Photonics Group in the Physics Department at Imperial in 2002, where he became Professor in 2009.