Events & Seminars

The butterfly effect in quantum cascade lasers: Why and What? February 28, 2019, 4:00 pm Frédéric Grillot Frédéric Grillot Professor, Télécom ParisTech

ABSTRACT: The quantum cascade (QC) laser is a promising light source based on resonant tunneling and optical intersubband transitions between quantized conduction band states. In these semiconductor lasers, the principles of operation arise from the quantum engineering of electronic energy levels and tailoring of their wavefunctions [1]. The opportunity given by the broad span of wavelengths that QC lasers can achieve, from mid-infrared to terahertz, leads to a wide number…

Integrated-Photonics Frequency Combs: Precision Metrology, Optical Synthesis, and Nonlinear Optics on the Nano-Scale January 25, 2019, 10:00 am Image of Tara Drake Tara Drake NRC postdoc fellow, National Institute of Standards and Technology

The invention of optical-frequency combs has transformed the fields of precision metrology, spectroscopy, and electronic/photonic signal generation. Now, a new and incredibly promising platform for frequency combs has emerged—one in which phase coherent combs are generated in nanofabricated ring resonators using quantum nonlinear photonics. I will present our work designing the first octave-…

Integrated Nanophotonic Technologies for Quantum Information Science January 23, 2019, 10:00 am Image of Galan Moody Galan Moody Research Scientist, National Institute of Standards and Technology (NIST)

Abstract: Quantum information science (QIS) technologies for computing, communications, sensing, and metrology rely on the ability to generate and detect non-classical information using light and matter. Photonics plays a central role in QIS because of the inherent scalability and low-loss, high-speed transmission of light. Yet, despite its ubiquitous presence, there are no high-…

Monolithic integration of III/V-based functionalities to CMOS-based Si-micro- and nanoelectronics December 8, 2017, 9:00 am Wolfgang Stolz Wolfgang Stolz Professor, Philipps-Universität Marburg; Co-Founder of NAsP III/V GmbH

Abstract: In recent years, the monolithic integration of III/V-semiconductor materials and heterostructures on CMOS-compatible (001) Si-substrate is gaining increasing interest for the realization of novel integrated circuits with improved electronic, optoelectronic or photonic functionalities. The principal challenges of the III/V-material integration on CMOS-compatible (001) Si-substrates will be reviewed and possible solutions for the high-quality…

Semiconductor quantum dot lasers: Why are they so quantum? November 20, 2017, 2:00 pm Frédéric Grillot Frédéric Grillot Professor, Télécom ParisTech, France, Research Professor, University of New-Mexico, USA

Abstract: By the reduction of semiconductor structure dimensionality, from bulk to quantum-well and finally to quantum-dots (QDs), we gain in control over the energetic distribution of carriers and their interaction with light [1]. While in bulk material many electron states, which are distributed in energy and momentum, have to be occupied, only a few states near the bandgap can contribute to the optical gain in lasers. Over the last past years, tremendous efforts have been…

Advances in Energy Efficiency through cloud and ML October 20, 2017, 4:30 pm Urs Hölzle Urs Hölzle Senior Vice President, Technical Infrastructure & Google Fellow

Abstract: Today, the IT industry accounts for about 2 percent of total greenhouse gas emissions, comparable to the footprint of air travel. This footprint includes everything from datacenters and servers to networks and client equipment like laptops and printers. More and more information is being generated every day, and more and more consumers and enterprises are processing this information every day. Will IT emissions eclipse air travel one day soon?
I think the…

2D material-based layer transfer based on remote epitaxy & uniform epitaxial RAM towards large-scale neuromorphic arrays July 14, 2017, 10:00 am Image of Dr. Jeehwan Kim Jeehwan Kim Massachusetts Institute of Technology

Bio: Professor Jeehwan Kim joined the Mechanical Engineering faculty at Massachusetts Institute of
Technology in September 2015 and the Materials Science and Engineering in February 2016 as a
joint appointment. He is a Principal Investigator in Research Laboratory of Electronics at MIT.
Prof. Kim's group focuses on innovation in nanotechnology for electronic/photonic/energy
applications. Before joining MIT, he was a Research Staff Member at IBM T.J.…

Semiconductor Nanowires for Optoelectronic and Energy Applications June 9, 2017, 12:00 pm Professor H. Hoe Tan H. Hoe Tan Head of the Department of Electronic Materials Engineering at the Research School of Physics and Engineering, The Australian National University

Bio: Professor H. Hoe Tan is currently the Head of the Department of Electronic Materials Engineering at the Research School of Physics and Engineering, The Australian National University. He received his B.E. (Hons) in Electrical Engineering from the University of Melbourne in 1992, after which he worked with Osram in Malaysia as a quality assurance engineer. In 1997, he was awarded the PhD degree from the Australian National University for his dissertation on "Ion beam…

High-Resolution Quantitative Cathodoluminescence (CL) for Defect Metrology in Semiconductors April 7, 2017, 8:30 am Image of Samuel Sonderegger Samuel Sonderegger CEO & Co-Founder of Attolight AG

Abstract: High spatial resolution spectroscopic information may be acquired by using an electron beam in a modern scanning electron microscope (SEM), exploiting a phenomenon called cathodoluminescence (CL). CL can be used to perform non-destructive analysis of a broad range of materials comprising insulators, semiconductors and metals. This approach offers several advantages over usual optical spectroscopy techniques. The multimode imaging capabilities of the SEM enable the…

More-than-Moore with Integrated Silicon-Photonics March 30, 2017, 4:00 pm Image of Vladimir Stojanovic Vladimir Stojanovic Associate Professor, Electrical Engineering & Computer Science, UC Berkeley

Abstract: In this talk we'll present the latest results on the integration of silicon-photonic interconnects into a monolithic platform (45nm SOI logic process and bulk CMOS memory periphery process). These include world's first microprocessor communicating to the outside world with monolithically integrated Si-Photonic devices, as well as the first demonstration of photonics in a bulk CMOS process. We’ll also illustrate some critical aspects of this technology that need to…

Nonlinear Optics in AlGaAs: Past, Present and Future Prospects March 13, 2017, 12:00 pm Image of J. Stewart Aitchison J. Stewart Aitchison University of Toronto, Department of Electrical and Computer Engineering

Abstract: The III‐V semiconductor AlGaAs is an ideal nonlinear optical material. It has large second and third order nonlinearities, a low two‐photon absorption coefficient at the half band gap and allows for the easy fabrication of integrated optical devices. In additoon, AlGaAs can be used directly integrate photodiodes, modulators and passive optical elements on the same chip as the nonlinear elements. This talk will highlight the benefits of this nonlinear material…

Nano Research at the University of Duisburg-Essen: An Overview March 1, 2017, 4:00 pm Tobias Teckentrup Tobias Teckentrup Managing Director, Center for Nanointegration Duisburg-Essen (CENIDE)

Abstract: The Center for Nanoinetgration Duisburg-Essen (CENIDE) is a research center that focuses on nanoscience as the main research area of the University of Duisburg-Essen (UDE, Germany). Since 2005, CENIDE links the activities in natural science, engineering and medicine at the UDE that deal with the nano dimension. The experience of more than 65 working groups is divided into five research areas: Dynamic Processes in Solids, Gas-phase Synthesis, Magnetism,…

Compliant III-V On (001) Si Substrates for Direct Laser Growth January 5, 2017, 4:00 pm Image of Dr. Kei May Lau Kei May Lau Fang Professor of Engineering and Chair Professor, Hong Kong University of Science and Technology (HKUST)

Abstract: Integrating high-performance III-V devices on the mature silicon platform has been a long pursuit over the past few decades. Direct epitaxial growth offers an alternative technology to bonding.  Using nano-patterned Si substrates, we created III-V on silicon templates with low defect density and smooth surface morphology for laser growth.  Such antiphase-domain (APD)-free III-V on silicon compliant templates with high crystalline quality (benchmarked by narrow XRD…

Optofluidic Integration of Hollow-Core Waveguides for Chip-based Biomolecule Analysis December 15, 2016, 4:00 pm Image of Dr. Holger Schmidt Holger Schmidt Narinder Singh Kapany Chair of Optoelectronics and Associate Dean for Research for the School of Engineering at UC Santa Cruz

Abstract: Integrated photonic devices have traditionally been designed for data communications using exclusively solid-state materials. However, a vast area of potential applications, in particular in the life sciences, involve interactions of light with liquids and gases. Recently, a number of optofluidic approaches have been considered that are aimed at integrating such non-solid media with chip-scale photonic structures. We have developed a versatile, planar photonic…