Events & Seminars

Characterizing and Controlling the Impact of Dislocations on the Reliability of InAs Quantum Dot Lasers

Dissertation Defense

Eamonn Hughes

WEDNESDAT, November 29th AT 10:00AM

ZOOM MEETING - Click Here to Join

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We review advances in the timing stabilization of self mode-locked and passively mode-locked
frequency comb semiconductor lasers in the infrared spectral range. Prospects of pulse train timing and
amplitude stability control, intermode beat frequency or pulse repetition rate agility, timing
synchronization and high peak power optical pulse generation are discussed. A mechanism responsible
for the timing stability control and intermode beat frequency or repetition rate…

Nanoscale Foundries: Electronics, Photonics, Ionics, Fluidics

Dr. Rajeev Ram

 Department of Electrical Engineering & Computer Science, MIT

Modern silicon fabs routinely produce functional electrical components for a few dollars at part counts exceeding

billions per year and a complexity rivaling the human genome. The productivity of these fabs is ensured by design

rules that govern the structures that constitute these systems. These…

Abstract: Integrated electronic-photonic co-design can profoundly impact both fields resulting in advances in several areas such as energy efficient communication, signal processing, imaging, and sensing. Examples of integrated electronic-photonic co-design may be categorized into two groups: (a) electronic assisted photonics, where integrated analog, RF, mm-wave, and THz circuits are employed to improve the performance of photonic systems, and (b) photonic assisted electronics, where…

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…

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-…

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-…

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…

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…

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…

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.…

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…

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…

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…

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…

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,…

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…

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…