Thursday, Nov. 7th | 10:00 - 11:00 am | ESB 2001 Abstract: Graphene has emerged as an alternative saturable absorber to other semiconductors due to its nearly constant broadband absorption of 2.3%. It has been shown that graphene and graphene-based nanomaterials can be used as efficient saturable absorbers to generate ultrashort pulses from lasers operating in the near- and mid-infrared. However, the 2.3% absorption of the monolayer graphene introduces operational challenges to the lasers with low gains. To obviate such challenges, the Fermi level position of the graphene can be varied to control the amount of absorption at the desired wavelength. For this purpose, chemically- or electrostatically-doped novel graphene architectures with reduced optical insertion losses can be used to optimize the power performance of the femtosecond lasers. In this talk, the use of carbon-based saturable absorbers to generate ultrashort pulses from solid-state lasers will be presented and their current drawbacks will be discussed. This will be followed by the overview of the possible approaches, which have been demonstrated to shift the Fermi level of graphene to control the amount of absorption at the desired wavelength. At this point, the voltage-controlled graphene-based supercapacitor architectures proposed by our groups will be demonstrated and the femtosecond pulse generation results obtained with these devices will be discussed. In the remainder part of the talk, Dr. Baylam will give information about the opportunities provided by The Optical Society (OSA) to the graduate students and early career researchers. Snacks and Coffee will be provided.
Fri. Nov 1, 2019 | 3:00 - 4:00 pm | Elings 1605 Women in Photonics Week 2019 |
Event |
Date and Time |
Location |
Add to Calendar |
Girls Inc. : LaserComm Activity |
Thurs. Oct. 17 4:15-5:15 pm |
UCSB |
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SPIE Visiting Lecturer Prof. Andrea Armani |
Fri. Oct. 18 12:00 - 1:00 pm |
UCSB: ESB 2001 |
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Freedom Photonics Tour |
Thurs. Nov. 21 3:30 - 5:30 pm |
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UCSB Nanofab Tour |
Sat. Oct 19 1:00 - 3:00 pm |
UCSB: ESB ground floor |
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Megan Birney, President of Unite to Light |
Thur. Oct. 24 5:00 - 6:00 pm |
UCSB: ESB 2001 |
- |
I HEART STEM Conference |
Sat. Nov 9 9:30 am - 3:45 pm |
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SPIE Visiting Lecturer Prof. Andrea Armani
Nanomateial-Enhanced Integrated Photonics
Abstract: Integrated photonics offers a potential alternative to integrated electronics, with reduced heating and faster data rates. However, to achieve many of the desired performance metrics, it is necessary to combine disparate material systems. Heterogeneous integration is plagued by challenges, including different lattice constants, thermal expansion coefficients, and fabrication compatibilities, all of which can impact the final device performance ad lifetime. Therefore, new materials and material systems as well as fabrication methods are desired. One approach is to combine the conventional top-down fabrication methods and optical materials, such as silica and silicon, with bottom-up fabrication and nano-materials. These hybrid systems provide access to optical behavior and performance not attainable with conventional approaches. This talk will present several of the new integrated hybrid photonic devices being developed in the Armani Lab, including approaches based on nonlinear organic small molecules and plasmonic nanoparticles to develop Raman lasers and frequency combs.
Freedom Photonics TourThurs. November 21, 2019 | 3:30 to 5:30 pm |
The tour, led by the women scientists at the company, will show their nanofabrication facility along with a short discussion of photonics and hands-on activities.
Proof of U.S. Persons required:
ALL tour attendees must bring ONE of the following IDs:
(1) U.S. Passport
(2) U.S. Naturalization Certificate
(3) Permanent Resident/Green Card
(4) U.S. Birth Certificate AND either Photo ID or Social Security card
Note: For parents or chaperones, a driver's license is NOT valid proof. Yes, even children need this proof.
UCSB Nanofab Tour
1:00 PM – 2:00 PM and 2:00 PM – 3:00 PM
Expert users lead tours of the NanoFab in groups of 5, where everyone was gowned up in a "bunny suit" before entering the high-tech lab.
Closed-toed shoes required to enter (eg. no sandals or flip-flops).
Megan Birney, President of Unite to Light
Throughout her career Megan has focused on increasing access to clean, renewable energy. She started her career at the Community Environmental Council where she ran the Energy Efficiency and Renewable Energy Programs, including creation of Solarize, a residential group-purchasing program in California. While there she advocated for renewable energy projects and policies leading to over 1 GW of solar in the Central California region. Then Megan served as Director of Strategic Affairs and Product Manager for a commercial solar financing company that was aiming to address the financing gap for nonprofits and small businesses. Megan is also a Water Commissioner for the City of Santa Barbara. She has a Masters in Public Policy from the University of Southern California, and a BA in Sociology from the University of California, San Diego. Megan has taught a courses on energy sources, uses and issues through the University of California extension program.
Photonics and Global Aid & Development: the Power of Solar Lights
Unite to Light, a nonprofit founded at UCSB, manufactures and distributes solar lights and solar power to people living without electricity. Hear from President & CEO Megan Birney about how the organization was founded, the innovation of their lights, and the impact around the world.
I HEART STEM Conference
The talk will describe how a high performance PIC including arrays of these devices can be utilized for the processing of a phased array sensor to provide Multiple-Channel Simultaneous RF Beamforming, and describe potential commercial markets for these technologies, including automotive LIDAR systems, analog photonic links and RF Beamforming for 5G systems
The 2019 Photonics Society Summer BBQ was filled with good food and drinks. Thanks to everyone who came!
Matthew Wong DenBaars group Materials Dept, UCSB | High Efficiency III-Nitride Mirco-Light-Emitting Diodes for Display Applications Micro-light-emitting diodes (µLEDs) with high energy efficiency are desired for a variety of display applications, including virtual reality (VR) and augmented reality (AR) near-eye displays. Although outstanding performances in different display aspects have been demonstrated with InGaN µLEDs, there are several challenges for commercialization. In this talk, two main issues, namely size-dependent efficiency and mass transfer of µLEDs, will be addressed and some promising solutions will be discussed. |
Takako Hirokawa Schow group ECE Dept, UCSB | Energy Efficiency Analysis of Coherent Links for |
Tuesday June 4th, 6pm at Corwin Pavilion @ UCSB
See the event page for more info:
SB Photonics Banquet 2019
Kristina Davis Mazin group Physics Dept, UCSB | Coherent Differential Imaging Techniques for MKID Detectors The field of direct imaging of exoplanetary systems allows astronomers to gain both photometric and spectroscopic analysis of these exoplanetary systems. I will present a technique I call Heterodyne Optical Phase Probe (HOPP) that measures the phase change of an incoming heterodyne signal incident on the kinetic inductance detector array as the deformable mirror is actuated. By measuring the phase response, we can improve our models of the DM surface shape under a variety of optical conditions, and have a better calibration of how to scale the offset positions we feed the DM when performing speckle nulling. |
Chris Zollner Nakamura group Materials Dept, UCSB | MOCVD growth of AlN on SiC substrates for deep-UV optoelectronics: an inside the box approachMOCVD growth of high-quality GaN on sapphire substrates is vital to today's blue LED industry, but the same methods cannot be applied to AlN/sapphire which is needed for deep-UV optoelectronics. We have developed a novel approach to MOCVD growth of AlN on SiC with quality comparable to industrial GaN/sapphire, and demonstrated UV-LEDs emitting at 280nm. |
Dr. Steven DenBaars Mitsubishi Distinguished Professor Materials Distinguished Professor Electrical & Computer Engineering |
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
Low Threshold 1.55 um Quantum Dash Microring Lasers We report the first room-temperature-continuous-wave (CW) operation of electrically-injected InAs quantum-dash microring lasers emitting at 1.55 µm telecom window. The microrings sustain CW lasing up to 55°C, while the lowest threshold current density is 528 A/cm2 . |
Quantum dot devices on silicon grown by MOCVD Direct heteroepitaxy of III-V quantum dots (QDs) is promising for achieving a monolithic laser source for silicon photonics. QDs are believed to be less sensitive to defects than quantum wells, and also offer desirable characteristics for high temperature operation and reduced sensitivity to reflection, because of the 3D carrier confinement of individual QDs. In this talk, I will introduce my research on growth of aluminium-free InAs/GaAs quantum dot laser structure on CMOS-compatible (001) by MOCVD, and some initial fabrication works for both electrically and optically devices. |
Pizza will be provided!
nonlinear switches using 2D materials presents an attractive direction for robust next generation quantum photonic technologies.
From subsea fiber cables to short-reach switch interconnects, opto-electronics is a key technology for hyperscale data center networks. As performance requirements increase, photonics moves deeper into the network replacing copper for shorter distances. The next move for photonics is to distances of less than 3m for in-rack applications. This talk will describe how the scale of data-bandwidth growth has challenged what is possible with traditional networks and where the next opportunities for innovation lie. |
Think small: developing color centers in crystals for nanoscale optical sensors of fields and forces
4/7/2019
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.
Biography
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.
Monolithically-Integrated Photoreceiver with Cherry-Hooper TIA in BiCMOS TechnologyIn this talk, we report a monolithically-integrated photoreceiver with a pseudo-differential Cherry-Hooper trans-impedance amplifier (TIA) in a 250 nm BiCMOS process. High sensitivity 50 Gbps operation is demonstrated, and the TIA architecture is analyzed. |
A Low-noise High-channel-count 20 GHz Passively Mode Locked Quantum Dot Laser Grown on SiLow cost, small footprint, highly efficient and mass producible on-chip wavelength-division-multiplexing (WDM) light sources are key components in future silicon electronic and photonic integrated circuits (EPICs). We present here, for the first time, a low noise high-channel-count 20 GHz passively mode locked quantum dot laser grown on CMOS compatible on-axis (001) silicon substrate. The laser demonstrates a wide mode locking regime in the O-band. The 3 dB optical bandwidth of the comb is 6.1 nm (containing 58 lines, with 80 lines within the 10 dB bandwidth). Utilizing 64 channels, an aggregate total transmission capacity of 4.1 terabits per second is realized by employing a 32 Gbaud Nyquist four-level pulse amplitude modulation format. The demonstrated performance makes the laser a compelling on-chip WDM source for multi-terabit/s optical interconnects in future large scale silicon EPICs. |
Pizza will be provided!
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