Friday, May 31st | 12:00 pm | Elings 1605
Friday, May 17th | 12:00 pm | ESB 2001
Fluency Lighting Technologies is an early stage start-up company developing technology out of UC Santa Barbara. At Fluency, we are creating next-generation bright and narrow-beam light sources for highly efficient illumination, using laser technology and materials design. Our focus is the development of low-cost, optical platforms that convert laser diode emission into high-quality white light in various light levels, beam angles, and color temperatures, designed for customer-driven metrics, in applications where energy-saving LED technology is not used because of the limited light output from an LED.
Refreshments will be provided
Thursday, May 16th | 12:00 pm | Elings 1601
In recent years, widely tunable micro-electro-mechanical systems vertical cavity surface-emitting lasers (MEMS-VCSELs) have found commercial application in swept source optical coherence tomography medical imaging and also show considerable promise in metrology and spectroscopy. These devices exhibit fractional tuning ranges of >11% of the center wavelength, wavelength tuning repetition rates over full tuning range of >1MHz, and clean single-mode operation. These properties, in conjunction with small size and wafer scale fabrication and testing, promise an economical optical source that can impact sensing applications from the visible to the mid-infrared.
Refreshments will be provided
Wednesday, May 15th | 12:00 pm | ESB 1001
In this talk I will highlight the history of GaN research at UCSB, and some of the key breakthroughs and technologies developed by the faculty, students and staff. Starting with one MOCVD system, UCSB Faculty were the first University world-wide to achieve a blue GaN Laser in 1996. In 2000, Prof. Shuji Nakamura joined the Faculty and along with Prof. DenBaars, Prof. Speck and Prof. Mishra co-founded the Solid State Lighting and Energy Electronics Center (SSLEEC), which has now become one of the largest academic GaN based Photonic and Electronic research centers in the world. SSLEEC has played a key role in developing numerous breakthroughs, some of which have led to the realization of high-efficiency Solid-State Lighting, which the Dept. of Energy estimates will save the equivalent annual electrical output of about fifty 1,000-megawatt power plants.
Looking into the future we see next generation GaN Laser Diode based solid state lighting as impacting high brightness specialty lighting. We have demonstrated laser based white lighting with luminous efficacies of 87 lm/watt, and over 1000 lumens from a single emitter. In addition, tunnel junctions have been employed to achieve vertical cavity surface emitting lasers (VCSELs) in the blue spectral region. Blue and green lasers and Micro-LEDs based on GaN materials are expected to enable new full color projections displays for cinema, office and augmented reality (AR) applications.
Refreshments will be provided
Thursday, May 9th | 12:00 pm | Elings 1601
Chris will discuss next-generation optical interfaces for large scale datacenters, including Intensity Modulated Direct Detection and Coherent technologies at 100, 200, 400 and 800 Gb/s rates. He will show several examples of how applying insights gained from previously successful applications can lead to flawed conclusions about different applications. If he is persuasive, students will no longer trust what they are taught by their professors and other experts.
Friday, May 3 | 12:00pm | Elings 1605
Pizza will be provided!
Friday April 26th | 12:00 pm | Elings 1605
Two-dimensional Van der Waals materials have emerged as a very attractive class of optoelectronic material due to the unprecedented strength in its interaction with light. In this talk I will discuss approaches to realize quantum photonic devices by integrating these 2D materials with microcavities, and metamaterials. I will first discuss the formation of strongly coupled half-light half-matter quasiparticles (microcavity polaritons) and their optical and electrical control in the 2D transition metal dichacogenide (TMD) systems. Prospects of realizing condensation and few photon nonlinear switches using Rydberg states in TMDs will also be discussed. Following this, I will discuss the broadband enhancement of light-matter interaction in these 2D materials using photonic hypercrystals and chiral metasurfaces. Finally, I will talk about room temperature single photon emission from hexagonal boron nitride and the prospects of developing deterministic quantum emitters using them through strain engineering. The realization of room temperature single photon emitters and few photon
nonlinear switches using 2D materials presents an attractive direction for robust next generation quantum photonic technologies.
Tuesday, April 23rd | 12:00 pm | Elings 1601
Today zettabytes of data are generated and nearly doubled every two years. The conventional microprocessor is reaching its physical limitation and cannot keep up with the exponential growth in rich data. This leads to the increased demands on memory systems due to their frequent access patterns between microprocessors and memories. High speed, low energy and high sensitive optical data links are desirable for data transmission between multicores, microprocessors and memories in the new data center and high performance computer architectures. I am going to talk about the silicon photonics efforts in developing low energy high speed optical links in Hewlett Packard Labs, including the development of low voltage SiGe avalanche photodiodes, as well as photonic links.
Monday, April 15 | 12:00pm | Elings 1605
Think small: developing color centers in crystals for nanoscale optical sensors of fields and forces
Friday, April 12 | 12:00pm | Elings 1605
From mapping inter-cellular mechanical interactions in the immune system to imaging magnetic phenomena in condensed matter systems, there is a growing need for noninvasive sensors with high spatial resolution. Color centers in crystals such as alkaline-earth upconverting nanoparticles (UCNPs) and the nitrogenvacancy (NV) center in diamond are an exciting class of sensors for highresolution imaging because of their optical readout, nanoscale size, and robust hosts. The first part of this talk will discuss UCNPs for mechanical force sensing in biological applications. UCNPs consist of a ceramic host doped with lanthanides (Yb3+ and Er3+). They operate by absorbing low energy infrared photons and emitting higher energy visible photons. Mechanical forces cause a change in the crystal symmetry and spacing of the dopant atoms, which results in a change of emission intensity and color. We have recently detected 27 nN forces with our UCNPs, a requisite for detecting inter-cellular forces in the immune system. The second half of this talk will discuss using the NV center in diamond as a magnetic force sensor. Through careful materials science studies in the Jayich lab, we created NV ensembles approaching the NV dipolar interaction limit of sensitivity. Using these NV ensembles, we imaged magnetic structure in CoTiSb.
Monday March 11th, 11am, ESB 1001
The continuing growth in demand for bandwidth (from residential and business users), necessitates significant research into new advanced technologies that will be employed in future broadband communication systems. Two specific technologies, becoming increasingly important for future photonic systems, are wavelength tunable lasers and optical frequency combs. Although these topics have been studied for over two decades their significance for the development of future ultra-high capacity photonic systems has only recently been fully understood. Wavelength tunable lasers are currently becoming the norm in optical communication systems because of their flexibility and ability to work on any wavelength. However, as their operating principles are different to standard single mode lasers they can effect how future systems will operate. For example as optical transmission systems move towards more coherent transmission (where the data is carried using both the intensity and phase of the optical carrier), the phase noise in these tunable lasers will become increasingly important. Optical frequency combs also have many applications for future photonics systems, and for telecommunications they can be used to obtain the highest spectral efficiency in optical transmission systems by employing the technology of optical frequency division multiplexing (OFDM), and also for generation of high frequency RF signals in future 5G networks. Wavelength tunable lasers and optical frequency combs are thus topics at the leading edge of current photonics systems research, and their detailed understanding promises new applications in all-optical signal processing, optical sensing and metrology, and specifically telecommunications. This talk will focus on the development and characterization of various wavelength tunable lasers and optical frequency combs, and then outline how these sources can be employed for developing optical transmission systems and networks which make the best use of available optical spectrum.
Liam Barry received his BE (Electronic Engineering) and MEngSc (Optical Communications)
degrees from University College Dublin in 1991 and 1993 respectively. From February 1993 until January 1996 he was employed as a Research Engineer in the Optical Systems Department of
France Telecom's Research Laboratories (now known as Orange Labs) in Lannion, France, and as a result of this work he obtained his PhD Degree from the University of Rennes in France. In February 1996 he joined the Applied Optics Center in Auckland University, New Zealand, as a Research Fellow and in March 1998 he took up a lecturing position in the School of Electronic Engineering at Dublin City University, and established the Radio and Optical Communications Laboratory. From April 2006 until February 2010 he served as Director of The Rince Institute, an interdisciplinary research center with over 100 researchers. He is currently a Professor in the School of Electronic Engineering, a Principal Investigator for Science Foundation Ireland, and Director of the Radio and Optical Communications Laboratory. His main research interests are; all-optical signal processing, optical pulse generation and characterization, hybrid radio/fibre communication systems, wavelength tuneable lasers for reconfigurable optical networks, and optical performance monitoring. He has published over 200 articles in international peer reviewed journals, 250 papers in international peer reviewed conferences, and holds 10 patents in the area of optoelectronics. He has been a TPC member for the European Conference on Optical Communications (ECOC) since 2004, and a TPC member for the Optical Fibre Communication Conference (OFC) from 2007 to 2010, serving as Chair of the Optoelectronic Devices sub-committee for OFC 2010.
12:00 PM Friday, March 1st in Elings 1605
Pizza will be provided!
Thursday, Feb 28, 12 - 1 pm, ESB 1001
Refreshments will be provided
Friday, Feb 8, 1 – 2 pm, ESB 1001
More than a billion individual VCSELs were deployed before 2017 as optical sources within short-reach optical interconnects as well as for position sensing. In 2018, laser manufacturing began the era of 2D VCSEL arrays. As a result more than a billion new VCSELs were added in a single year to provide new functionality for consumer electronics products. In this talk I will report on the development of coherently coupled VCSEL arrays which may enable new VCSEL applications. I will discuss the physics of operation for antiguided photonic crystal VCSEL arrays, and will show their potential application for electronic beam steering and high speed digital data transmission.
Friday, Jan. 25th at 12:00 PM in ESB 1001
Pizza will be provided
Coherent Ising machine: a photonic Ising model solver based on degenerate optical parametric oscillator network
Friday, Jan 18, 12 – 1 pm, Elings 1605
As various systems and networks in our society grow larger and more complex, analysis and
optimization of such systems are becoming increasingly important. Such tasks are classified as combinatorial optimization problems, which are generally difficult to solve with current digital computers. It is well known that combinatorial optimization problems can be converted to ground-state-search problems of the Ising model, a theoretical model for the interacting spins. Recently, several approaches to find solutions to the Ising model using artificial spin systems have been studied intensively. A coherent Ising machine (CIM) is one of such systems in which degenerate optical parametric oscillators (DOPO) pulses are used as artificial spins. By using a long-distance (typically 1 km) fiber cavity that contains a phase sensitive amplifier based on a periodically poled lithium niobate waveguide, we can generate thousands of DOPO pulses multiplexed in time domain. Since a DOPO phase only takes either 0 or p at above threshold, we can stably express an Ising spin with a DOPO by allocating phase 0 (p) as spin up (down). The “spin-spin interaction” can be implemented by using a measurement-feedback scheme, with which we can effectively realize mutual injection of lights among thousands of DOPO pulses. The networked DOPOs are most likely to oscillate at a phase configuration that best stabilize the whole network, which gives the solution to the given Ising problem. Based on this scheme, we realized a CIM with all-to-all-coupled 2000 DOPO pulses, by which we could find good solutions to 2000-node combinatorial optimization problems in less than 100 microseconds. In the talk, I will describe the basic principle and the experimental details of the CIM, as well as our effort for finding its applications.
Tuesday, Dec. 11th at 12:00 PM in Elings 3001
Pizza will be provided!
Tuesday Dec. 4th at 12:30 pm in ESB 1001
Pizza will be provided!
This is the start of the weekly student lecture series IEEE Photonics is hosting throughout Winter 2019! Ryan DeCrescent and Robert Zhang will be presenting their talks.
Wednesday November 28th, 2 pm, ESB 1001
Alex is an entrepreneur with a track record of building teams that take ideas from the research
laboratory through commercialization. Alex was a co-founder, the CEO, and Board Director
of Aurrion from 2008-2016 which was a fabless semiconductor company that developed photonic integrated circuits for data center networking applications. The business was acquired by Juniper Networks. Alex worked for IBM, Lawrence Livermore National Laboratory, and Intel prior to founding Aurrion. Alex earned his M.S & Ph.D. from UCSB and is an alumnus of the Harvard Business School Owner/President Management Program. In his downtime, Alex enjoys riding off road motorcycles, playing guitar, smoking meat and reading books. Alex loves spending time with his wife and daughter going to live shows, travelling and eating weird stuff.
Dr. Ken-Tye Yong
Director of the Bio Devices and Signal Analysis (VALENS)
School of Electrical and Electronic Engineering
Nanyang Technological University (NTU)
Tuesday, Nov. 20th, 3 - 4 pm, ESB 2001
Nanomaterials have been applied in healthcare applications such as cancer imaging, lymph node mapping and brain diseases therapy. These nanomaterials can be engineered to serve as a platform for challenges in highly sensitive optical diagnostic tools, biosensors, and guided imaging and therapy. The versatility of nanomaterials may provide the keys to improve diagnostics and therapy of human diseases. In this talk, we will highlight the use of nanomaterials with different sizes, compositions, and shapes for nanomedicine applications. This talk is intended to promote the awareness of past and present developments of nanomaterials in biomedical fields, the potential toxicity of nanomaterials, and the approaches to engineer new types of safe nanomaterials, whereby encouraging researchers to think about exciting and promising biophotonic and nanomedicine applications with nanomaterials in the future.
Thorlabs designs and produces a variety of optomechanical and optoelectronic components in 15 facilities around the globe. Thorlabs seeks to listen and serve its customers with over 20,000 products available.
Difficult STEM subjects explained by textbook solution videos taught by expert educators including Physics, Calculus, Chem, Bio, Econ, Math, Science and more!