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Apr 03

S&I 3: Semiconductor Lasers, is an integral part of the Science & Innovations technical program. Dan Wasserman, University of Illinois, Subcommittee Chair provides us with some insight on this year’s invited speakers, hot topics and trends in paper submissions.

Photo of Dan Wasserman CLEO S&I 3 Chair

Daniel M. Wasserman, S&I 3 Chair, CLEO: 2014

CLEO Team:              Can you review the talks that you got and were there any themes or any outstanding trends that you were able to discern?

Dan Wasserman:  This was another outstanding year for Semiconductor Laser submissions to CLEO. I think the whole committee was impressed not simply with the quantity of submissions, but more importantly the breadth and quality of these submissions.  I think that one of the trends we are seeing in the contributed submissions is a pushing of the accepted state-of-the-art for a wide range of semiconductor lasers, across a broad range of frequencies.

Many of the contributed talks will focus on ‘going big’: record output powers and high efficiency emitters.  We are seeing impressive examples of this at long wavelengths (mid-IR and THz) with Watt-level or greater powers, using a range of very clever approaches.  At shorter wavelengths, we will have exciting work demonstrating high power VCSELs and photonic crystal lasers.  Other talks focus on going small: nano-scale lasers and ultra-fast pulses.  Finally, we are very much looking forward to a number of papers focusing on integration of III-V laser materials with Si electronics and photonic integrated circuits.

Overall, S&I 3 will offer an impressive array of contributed talks, with a breadth and quality that is indicative of the very best in current semiconductor laser research.

CLEO Team:            Can you tell us a little bit about the Invited  & Tutorial Speakers for S&I 3?

Dan Wasserman: We are so honored to have a line-up of truly incredible speakers accept our invitations to present at CLEO: 2014.  Our tutorial, entitled “Dealing with Losses in Plasmonics and Metamaterials”, will be given by Professor Jacob Khurgin, from Johns Hopkins University, and will provide insight into a major challenge facing future nano-scale optoelectronics.  Anyone who has seen Prof. Khurgin present knows that we are in for a provocative and exciting tutorial!  Our invited talks are also quite exciting, and represent a broad cross-section of current cutting-edge semiconductor laser research.  Prof. Yoshi Yamamoto (Stanford/Tokyo) will be presenting exciting new results on electrically-driven exciton-polariton lasers and Dr. Richard Stevenson (Toshiba Research) will show the latest results on his group’s demonstration of quantum teleportation using entangled LEDs.  Prof. Geert Morthier (Ghent) will provide an overview of his group’s work integrating high-performance micro-lasers onto Si substrates for optical interconnect and logic applications, and Prof. Wolgang Stolz (Philipps University) will discuss his work on near-IR VECSELs grown by MOCVD.   Combined, our tutorial and invited speakers will provide an excellent picture of not only the cutting-edge state-of-the-art in semiconductor lasers, but a glimpse into what the future of semiconductor lasers may well look like!

CLEO Team:               Are there any talks, in particular, that you are looking forward to hearing? If so, why?

Dan Wasserman:       I am, of course, looking forward to all of our talks, it is going to be a very exciting conference this year.  That having been said, I am particularly excited to see recent results on high power long wavelength lasers in presentations from the Meyer group at NRL (high power emission from interband cascade lasers), the Botez and Mawst groups at Wisconsin  (leaky wave coupling of quantum cascade lasers for high power emission), and the Strasser and Unterrainer groups at TU Wien (demonstrating ~1Watt of power from THz quantum cascade lasers).  The demonstration of high power superluminescent emitters, from the Gmachl group at Princeton, will be another exciting presentation.  I will also be looking forward to presentations from Prof. Noda’s group (Kyoto) and Prof. Choquette’s group (UIUC) on high power (>1.5W) and coherently coupled photonic crystal lasers, respectively.  We are excited to have Prof Matsuo’s group (NTT) present recent results demonstrating electrically pumped photonic crystal lasers integrated onto Si substrates.  And finally, I am eager to see a pair of presentations from Prof. Keller’s group at ETH on ultrafast VECSELs and MIXSELs, respectively.                      

CLEO Team:               Thank you very much.

The CLEO Conference, sponsored by APS/Division of Laser Science, IEEE Photonics Society and the Optical Society received record breaking submissions in 2014. The Conference takes place in San Jose, CA, USA, 8-13 June 2014. Visit www.cleoconference.org for program and registration information.

Mar 26

Taking a look around an airport, bus station, or waiting room, you’re likely to notice a few differences between the scenes now as compared to those of ten or so years ago. One thing that might strike you is that the papery time killers that filled lounging areas from the past are now replaced with personal electronic devices. Thanks to a great number of innovations, including the sophistication of LCDs, LEDs, electronic ink, and microprocessors, portable devices for reading purposes and beyond are becoming ubiquitous.

However, you might notice another striking difference between then and now with respect to these typeface transporters. It’s probably a tiny daily burden you’ve learned to cope with over the years: you can’t exactly roll up your electronic device like your morning newspaper. And I wouldn’t recommend trying it, but go for it if you don’t believe me (disclaimer: I’m not buying you a new phone, tablet, e-reader, or whatever you just broke).

Luckily, there are always smart folks who see these issues, as well as a handful of others: Why can’t I wear my electronics and photonics on my skin? Why can’t I cram my devices into any arbitrary space I want? Why should I have to look at these things but not through them?

Thanks to many forward-thinking materials researchers, the answer to the above questions seems to be, “No reason, let’s make it happen!” So here we are in the age of developing flexible electronics and photonics. The difficulty in making devices flexible is probably pretty obvious: most materials we conventionally use are not flexible! However, that doesn’t mean we can’t make a materials change for some things. For example, polymers are very flexible, so any pieces we can make out of those types of materials could be very helpful. And it turns out for photonics, you can make emitters, modulators, filters, and waveguides out of such materials as well as other organic and inorganic materials.

Nevertheless, if you’re like me, you have a hard time parting with semiconductors. They’re just so good at what they do and doing it efficiently. Well, there’s not necessarily any reason to abandon our band-gap-having, crystalline friends. It’s just that they need to trim down a little, to relieve a bit of the strain. The amount the most stressed crystalline layer needs to stretch or compress upon a deformation is related to how many layers away it is from the neutral plane, where there is no strain. Translation: make the layer thin.

So now you can bend your semiconductor, and you have an efficient source flapping in the breeze. Unfortunately, if you left it just like this, it would fall apart in an instant, its thickness being measured in units of nanometers (hence, nanomembranes). That’s why techniques have been developed to put these membranes on more stable yet flexible substrates. Enter again polymers. Two methods dominate at this time: transfer printing and direct patterning. Transfer printing is a process in which devices are fabricated and then bonded to the flexible substrate. This allows one to put a multitude of different devices, possibly made of different materials, on a single substrate. On the other hand, direct patterning utilizes deposition of a material on the substrate and then etching steps to define the devices. Although often less versatile than transfer printing, direct patterning is another robust method of making this flexible hybrid platform.

General process illustration for crystalline semiconductor membrane release, transfer and stacking. (a) Begin with source material (e.g., SOI, GeOI, III-V multi layers with a sacrificial layer). Metallization can be applied here, if needed. (b) Pattern top layer into membrane (or strip forms) down to the sacrificial layer. (c) Release membrane by undercutting the sacrificial layer. (d) Fully released membrane settles down on the handling substrate via van der Waals force (“in-place bonding”). Direct flip transfer: (e1). Apply glue on host (e.g., flexible) substrate and attach it to the handling substrate. (f1) Lift-up the host substrate and flip to complete the transfer. Glue can be dissolved if needed. Stamp-assisted transfer: (e2) Bring a stamp (e.g., Polydimethylsiloxane, or PDMS) toward the handling substrate, press and lift-up. (f2) Apply the stamp with membrane attached to a new host substrate (which can be coated with glue, but not necessary). (g2) Slowly peel off the stamp or remove the stamp with shear force, leaving the membrane to stay on the new host substrate. Multiple layers can be applied by repeating (a)-(f1) or (a)-(g2). (Juejun Hu, Lan Li, Hongtao Lin, Ping Zhang, Weidong Zhou, and Zhenqiang Ma, "Flexible integrated photonics: where materials, mechanics and optics meet [Invited]," Opt. Mater. Express 3, 1313-1331 (2013))
 http://www.opticsinfobase.org/ome/abstract.cfm?URI=ome-3-9-1313)

General process illustration for crystalline semiconductor membrane release, transfer and stacking. (a) Begin with source material (e.g., SOI, GeOI, III-V multi layers with a sacrificial layer). Metallization can be applied here, if needed. (b) Pattern top layer into membrane (or strip forms) down to the sacrificial layer. (c) Release membrane by undercutting the sacrificial layer. (d) Fully released membrane settles down on the handling substrate via van der Waals force (“in-place bonding”). Direct flip transfer: (e1). Apply glue on host (e.g., flexible) substrate and attach it to the handling substrate. (f1) Lift-up the host substrate and flip to complete the transfer. Glue can be dissolved if needed. Stamp-assisted transfer: (e2) Bring a stamp (e.g., Polydimethylsiloxane, or PDMS) toward the handling substrate, press and lift-up. (f2) Apply the stamp with membrane attached to a new host substrate (which can be coated with glue, but not necessary). (g2) Slowly peel off the stamp or remove the stamp with shear force, leaving the membrane to stay on the new host substrate. Multiple layers can be applied by repeating (a)-(f1) or (a)-(g2). (Juejun Hu, Lan Li, Hongtao Lin, Ping Zhang, Weidong Zhou, and Zhenqiang Ma, “Flexible integrated photonics: where materials, mechanics and optics meet [Invited],” Opt. Mater. Express 3, 1313-1331 (2013))
 http://www.opticsinfobase.org/ome/abstract.cfm?URI=ome-3-9-1313)

With these methods, one can make a number of photonic (and electronic devices). And there are some interesting avenues for exploration. For example, despite the strain-mitigation provided by thinning semiconductor membranes, it does not provide strain-elimination. The presence of strain alters the electronic and photonic properties of semiconductors, and therefore one can make tunable devices through flexing the material. However, this isn’t always a good thing; it creates a tough problem to solve when you want an extremely stable device under bending stress.

As hopefully you can see, this is a very exciting and active area of research. There are many open research questions and progress is continuing. If this topic catches your interest and you’re attending CLEO 2014, a great opportunity to learn more is from an expert! John Rogers from the University of Illinois at Urbana-Champaign will be giving a tutorial on flexible photonic devices. So be sure to check it out!

 

Disclaimer: Opinions, interpretations, conclusions, and recommendations are those of the author and are not necessarily endorsed by the United States Government and MIT Lincoln Laboratory.

Mar 21

Applications & Technology (A&T) is a key conference at CLEO: 2014, exploring the evolution of newly discovered technologies previously reported in CLEO: Science & Innovations as they are perfected and further developed to meet system and application requirements. New components, optoelectronics, and laser systems are demonstrated in real-world environments where innovative commercial technologies emerge.

Yu Chen, University of Maryland, Program Co- Chair provides an overview of this year’s A&T symposium and paper highlights.

CLEO Team:

Discuss the exciting lineup of symposia that are A&T related? What are some of the hot topics being covered?

Yu Chen:

This year we have organized a series of exciting symposia. The first two are focused on biomedical applications. The first one is Advances in Neurophotonics, organized by Drs. Nick Iftimia and Jin Kang. This symposium highlights the photonics technologies that enable mapping of brain function.  This is an important research area as highlighted by President Obama’s recent BRAIN Initiative. We have invited leaders in this field to share their frontier research. Topicscovered include optical coherence tomography and multi-photon microscopy for neuroimaging, high-resolution imaging of brain networks and diseases, and optogenetics.

Patient undergoing MEG. Wikipedia Commons

Patient undergoing MEG. Source: Wikipedia Commons

The second area of application is Molecular Imaging, which is an interdisciplinary area intersecting photonics technology and molecular medicine, with great potentials for early disease detection and personalized treatment. This year’s symposium, organized by Drs. Xavier Intes and Ali Azhdarinia, contains two sessions: one focuses on novel optical molecular imaging techniques, including near-infrared fluorescence imaging, Cerenkov radiation imaging, and photoacoustic imaging. The other session focuses on molecular probe development and clinical translation. The speakers are renowned scientists, clinicians, and industrial leaders that set the trend in this field.

The next two symposia are more technology oriented. The first one is Novel Light Sources and Photonic Devices in Optical Imaging, organized by Drs. Charles Lin, Nick Iftimia, and Ben Vakoc. This symposium highlights the advanced development of novel light sources and photonic technologies that enable biomedical imaging. Topics include novel light sources for nanophotonics-based OCT, as well as deep tissue multiphoton imaging and manipulation.

The next symposium has similar theme, but more focuses on Ultrashort Pulse Laser TechnologiesOrganizedby Drs. Ilko Ilev and Emma Springate, this symposium highlights the recent state-of-the-art development in ultrafast laser technologies for biophotonics and nanobiophotonics. Topics include ultrafast compact fiber lasers; tunable ultrafast visible, near- and mid-IR lasers; plasmonic nanobuble based integrated theranostics, and ultrafast laser induced ion beams for proton therapy.  

The next hot topic is Optofluidic Microsystems, organized by Drs. Ian White and Andreas Vasdekis. This symposium aims to highlight emerging trends in optofluidics and their application in microsystems.  This year’s program will feature an overview of the last ten years of optofluidics by one of the founding fathers of the field, Dr. Dmitri Psaltis, and will also project into the future by talks from current leaders in the field. Topics include optofluidic lasers and resonators, optofluidics for energy, and optofluidic particle manipulations.

CLEO Team:

What exciting papers did you receive for Applications & Technology?

Yu Chen:

We have a large affluence of papers for the light sources, resulting from the success of last year’s symposium on novel light sources. We also have papers focused on Neurophotonics, as stimulated by this year’s symposium. Our program includes new developments in OCT, multiphoton microscopy, and photoacoustic imaging, as well as clinical translation. Some of the example hot topics include adaptive optics for ophthalmology, point of care devices based on smart phones, minimally-invasive imaging technologies for disease diagnosis and therapy guidance, endomicroscopy, as well as multi-modal imaging combining OCT with fluorescence/confocal.

CLEO Team: Thank you


The CLEO Conference, sponsored by APS/Division of Laser Science, IEEE Photonics Society and the Optical Society received record-breaking submissions this year. The Conference takes place in San Jose, CA, USA, 8-13 June 2014.

For more information on CLEO: 2014 and the A&T program please visit www.cleoconference.org.

 

Mar 10

by David Norris,  Guest post

This is part 2 of a 3 part series post on the Controlled Light Propagation Incubator meeting at OSA headquarters in Washington, DC

Is it possible to look inside an object using only light reflected off the front?  Can you transmit more light through an attenuating medium by making it even thicker?  Could a bank verify your identity using the pattern of light scattered off your teeth?CT Scan image of brain

These tantalizing scenarios were among many presented during today’s meeting.  Though the focus remains on developing non-invasive deep imaging techniques for biological tissue, in particular using cameras and modulators placed only on the front side of a sample, the discussion also addressed more general questions on the theoretical limits of beam control and applications of scattering media to wide-field sensing.

Read more>>

Re-posted from The Optical Society Blog

Tagged with:
Mar 07

by David Norris,  Guest post

This is part 3 of a 3 series post on the Controlled Light Propagation Incubator meeting at OSA headquarters in Washington, DC

After a final session of talks on new developments in 3D imaging methods and funding opportunities, our host Jerome Mertz presented a timely summary of outstanding problems and possible solutions identified during this week’s IncubatorPropagationmeeting meeting:

  • The main challenge remains increasing the signal from a point of interest in the face of a large background of diffuse light. Tools such as spatial light modulators can impart a signal gain up to the number of pixels, but no further.  Multi-photon techniques hold promise but require compensation of both spectral and spatial degrees of freedom.
  • The utility of the so-called “memory effect” for scanning a focus across a sample was much discussed, but without clear consensus on whether it can work in the completely diffusive regime.  An alternative is sampling at multiple separated spots, either sequentially or in parallel.

Read More>>

Re-posted from The Optical Society Blog

Mar 07

by David Norris,  Guest post

This is part 1 of a 3 part series on the Controlled Light Propagation Incubator meeting at OSA headquarters in Washington, DC

example of biomedical imaging

Example of Biomedical imaging -source: wikipedia commons

The application of adaptive optics techniques–namely, optical wavefront shaping and phase modulation–to correct aberrations arising from highly scattering and disordered media holds tremendous promise for in vivo fluorescence imaging of biological tissue, and in particular the functional imaging of neural circuits. This topic has experienced an explosion of research activity in recent years, driven in large part by funding and interest from the BRAIN initiative, the Presidential focus aimed at mapping and unlocking the inner workings of the human brain. Following previous Incubator meetings in Optogenetics and Adaptive Optics, the organizers see today’s meeting as a natural next step.

Read more>>

Re-posted from The Optical Society Blog

Jan 31

By Shamsul Arafin

Since its successful and effective arrival in 1967, the Conference on Lasers and Electro-Optics (CLEO) has emerged as one of the biggest leading platforms for the researchers to be updated with recent progress in research and technology, especially with the latest worldwide advancements in optics and laser science. During such a long journey, CLEO has maintained the international prominence through its tradition of unparalleled and long standing excellence and leadership in showcasing the most significant scientific research milestones from laboratory to marketplace. Like every year, CLEO: 2014 (8-13 June in San Jose, CA, USA) is  getting ready to show its real glamour and activities for downtown san josethe optics researchers all around the world.

Just a few words to introduce myself: I am Shamsul Arafin, a postdoc working at UCLA. My research expertise is primarily in the area of semiconductor lasers, nanophotonic devices and heteroepitaxial growth of III-V on Si. I am a official blogger for CLEO: 2014. There are plenty of reasons for my excitement about this conference. These are so many that I’m not sure whether I can fit them all into this post.

First of all, CLEO: 2014 will not limit itself only to feature high quality research in the areas of: QELS- Fundamental ScienceScience & Innovations and Applications & Technology for six days, but also arrange  for special symposia, tutorials and business programming, all highlighting the latest research applications and market-ready technologies in all areas of lasers and electro-optics. In addition, this year CLEO will gather approximately 300 companies from around the globe introducing new products and demonstrating cutting-edge innovations.

Anything else? Yes, CLEO: 2014 will also provide opportunities for attendees to have some fun, catch up with fellow attendees, and meet new contacts in the industry. This is certainly a great opportunity to network and learn how to get the most out of the conference. Moreover, this event will bring together industry executives to share their business experience with young professionals and students.

Outside of the conference, one can discover the great Silicon Valley lifestyle, wide array of recreational options and experience several wonders that surround lovely Downtown San Jose, California.

You will not want to miss out on these limitless opportunities.  Looking forward to seeing you all there.

Nov 21
IMage of CLEO Program Co-Chair Eric Mottay

Eric Mottay, Amplitude Systemes, France, CLEO Program Co-Chair

Submit applications-related advancements in optics & laser science

 

The CLEO:2014  marketing team sat down with Eric Mottay, CLEO: Applications & Technology (A&T) Program Co-Chair to gain insight on the type of research presented at the A&T conference, the scope of the meeting and the benefits of submitting cutting-edge research to this high-quality, peer-reviewed conference.

CLEO Team:   What is the purpose of Applications and Technology Conference?

Eric Mottay:  Well, the Application and Technology Conference basically builds on the core strength of CLEO, which is the high scientific content, and  explores potential new applications which have the capability to extend into the industrial or commercial domain.  So it sits really at the frontier between the science and the application development work.

CLEO Team:    What type of work is submitted to Applications and Technology?

Eric Mottay:  Well – there are broad categories of research or applied research which can be submitted to the Application & Technology.  It can be industrial development, new emerging industrial applications.  It can also relate to new fields of interest like Bio Photonics or bio applications, for instance.  And also government-funded science, large projects, everything that is basically turning pure science into the application field.

CLEO Team:  What are the benefits of presenting your work at CLEO: 2014?

Eric Mottay:  CLEO: 2014 is a unique place where science meets applications, so by going to this conference, you’ll have some indications of the future of industry while being able to interact with the people making the science that will be the basis for these future directions.  So in this sense, it’s a fairly unique forum. There is a strict review process which ensures that all papers are of really top quality and there are not that many places where in a few days you can have such a broad view of science and emerging applications.

Note: Another important benefit to add is that every accepted paper is published in OSA’s digital library, Optics InfoBase, the largest peer-reviewed collection of optics and photonics. Presented research is also submitted to IEEE’s Xplore Digital Library and indexed in Ei Compendex, Scopus and several other indexing service partners.

 CLEO Team:    When is the deadline for the call for papers?

Eric Mottay:   The deadline for the call of papers for this conference is 22 January 2014, 17:00 GMT.  So it’s not that far off, so we can only encourage scientists, industry people, and Applications-oriented professionals to submit to this exciting conference. Just go to the CLEOconference.org website and you’ll be walked through it.  It’s a fairly easy process.

CLEO Team:      Wonderful.  Will the special symposia be accepting contributions during the call for papers period?

Eric Mottay:      As part of the Application and Technology Conference, we have a number of symposia, and symposia consist both of invited papers and selected number of contributed papers.  So some of the contributed papers can be accepted in various symposia in field as diverse as microphysics, lasers for consumer electronics, government, funded projects, et cetera.

CLEO Team:    As past subcommittee chair for the industry – industrial category, can you provide examples of prior submissions that were outstanding?

 Eric Mottay:      The privilege of serving as the committee chair for the industrial applications is that you get some advance knowledge of fascinating emerging applications.  So who would have thought – who would have thought, as I saw in a recent invited conference, that cold atoms and quantum gravimeters could lead to industrial applications in oil discovery or geology, for instance, or can you imagine building tiny devices out of glass which combine optical, mechanical, electrical, and photonic functions all on a single glass chips?  That’s just two examples of what the Application and Technology Conference can provide on the latest advancements.

CLEO Team:     CLEO also holds an Expo which provides timely business programming called Market Focus. Can you tell us why this type of programming would be of interest to CLEO: Applications & Technology attendees?

Eric Mottay:   Market Focus can indicate some future large areas or large directions that the technology or the industry should follow while the application and technology builds on the scientific background to explore new ways to go into these future directions.

CLEO Team:     Thank you.

Visit www.cleoconference.org to submit your research to CLEO: Applications & Technology. CLEO is also accepting research in QELS-Fundamental Science and Science and Innovations.For additional benefits on submitting and presenting your research to CLEO, visit http://www.cleoconference.org/home/submissions/.

View the Video for more insight on submitting to CLEO, the leading peer-reviewed conference on lasers and electro-optics.

Sep 23

Tom Hausken, Senior Advisor, Engineering and Applications at the Optical Society provides a brief update of the Industry.

National Photonics Initiative (NPI). The National Academies report, Optics & Photonics, Essential Technologies for Our Nation, recommended an industry-academia-government effort to promote photonics in the U.S, called the National Photonics Initiative. Many people worked over the winter to make it happen, and the NPI was officially launched on May 23 in a webcast. With the launch was the publication of a white paper intended to gather industry’s inputs and blessing to the overall effort. OIDA led the effort for the white paper on optical communications policy. Next, the Podesta Group (a leading lobbying firm in Washington) will help promote the NPI to policymakers.

Read More here

Jun 14

The last full day of CLEO: 2013 has concluded, and it was a particularly intense day to say the least. Besides a full day of contributed talks, invited talks, and tutorials, the postdeadline session filled up the evening. With that, we’re now heading into the final, shortened day of the conference.

As has been the case throughout the week, I had the opportunity to catch a number of nice contributed talks. However, I also had the chance to attend a couple of hour-long tutorials. The first was on photonics with graphene, presented by Prof. Tony Heinz. Prof. Heinz gave an excellent overview of the many interesting mechanical, electronic, and optical properties of graphene. These properties include extreme robustness to mechanical stress, very high electron mobilities, and a uniform optical absorption distribution over a wide bandwidth of photon energies (and how this can be altered with doping). He not only described these phenomena but also gave an intuitive explanation of the physics behind them. Due to these interesting properties, graphene is being explored for making electro-absorption modulators, photodetectors, and flexible electrodes.

The second tutorial I attended was a description of the challenges in realizing ultraviolet nitride semiconductor lasers and how to overcome them. Dr. Noble Johnson provided a description of two paths to UV nitride lasers: the direct use of wide bandgap AlGaN and frequency doubling of InGaN-based devices. There are challenges to both approaches, but it appears that good progress is being made. In the AlGaN system, it seems that the primary difficulty is with achieving electrical pumping due to poor electrical conductivity at wider bandgaps (higher Al concentration), which causes impossibly high threshold current densities at short wavelengths. Dr. Johnson presented a number of novel approaches to overcome this issue. He also described the second approach to reaching UV, which is with frequency-doubled vertical external cavity surface emitting lasers (VECSELs). As compared to a vertical cavity surface emitting laser (VCSEL), VECSELs provide the opportunity to reach higher powers and incorporate in-cavity nonlinear materials due to the presence of an external cavity. By utilizing this approach, it’s possible to leverage the now fairly common blue laser diode technology to reach the ultraviolet regime.

Nanoantenna array used for beamforming demonstrated by researcher at Massachusetts Institute of Technology (Sun et al., "Optical beamform engineering using phase and amplitude coded nanophotonic antenna arrays," presented at CLEO postdeadline session, 2013).

Nanoantenna array used for beamforming demonstrated by researchers at Massachusetts Institute of Technology (Sun et al., “Optical beamform engineering using phase and amplitude coded nanophotonic antenna arrays,” presented at CLEO postdeadline session, 2013).

Finally, in the evening were the postdeadline talks. As usual, these were very high impact talks that represented some cutting-edge developments. As is the case for the entire conference, the postdeadlines consisted of talks representing fundamental physics, applied science research, and practical applications. These three areas covered a wide variety of topics, including imaging and spectroscopy, integrated photonics, plasmonics, quantum optics, and the list goes on. I wish I had space enough to go through all the ones I got the chance to see, but for the sake of anyone reading this I’ll only mention the first one I saw as a teaser (if you didn’t have a chance attend the session, be sure to check out the abstracts and other materials that should be available online). This was work by Sun et al. from the Massachusetts Institute of Technology on beamforming using a photonic antenna array with tailored amplitude and phase profile. As the talk motivated, it is necessary to control both amplitude and phase in the near-field in order to form any arbitrary beam in the far-field. To this end, the group made a nanophotonic antenna array with an amplitude distribution determined by varying directional coupler lengths and phase that can be dynamically tuned with integrated thermal-optic tuners. The main result was the ability to produce a Gaussian-shaped far-field capable of being dynamically steered in two-dimensions.

Well, that closes my likely final blog entry of CLEO: 2013. It was a great meeting as usual, and I hope everyone enjoys the final partial day of the conference!

Disclaimer: Opinions, interpretations, conclusions, and recommendations are those of the author and are not necessarily endorsed by the United States Government and MIT Lincoln Laboratory.

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