8/19 Summer Colloquium Speaker Announcement

CHOI7_2On Tuesday, August 19th, the UR SPIE student chapter will be concluding its annual Summer Colloquium series. FREE PIZZA as well as other snacks and beverages will be provided!

Who: Joseph Choi

What:
Cloaking overview and ray optics cloaking at UR

 
Abstract:Cloaking background, including transformation optics and recent developments will be described initially. Then several fun ray optics invisibility cloaks from our group (
http://www.opticsinfobase.org/ao/fulltext.cfm?uri=ao-53-9-1958&id=281980) will be presented. To finish, challenges for current cloaking research will be discussed.

When: 8/19/2014  11:30 am – 12:30 pm

Where: Sloan Auditorium (Goergen 101)
Do you want to know what your peers are doing in their research? Want to network with people from the same field? Would you like to benefit from scholarships and conference discounts? Well, then join SPIE now! Just go to spie.org to register to become a student member of the U of Rochester chapter or send an email to urspie@gmail.com if you have any questions.

 

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8/12 Summer Colloquium Speaker Announcement

brooks_pOn Tuesday, August 12th the UR SPIE student chapter will be continuing its Summer Colloquium series. Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.

Who: Daniel Brooks
What: Precision Large Stroke Scanning System for Femtosecond Micromachining of Ophthalmic Materials
Date: 8/12/2014
Time: 11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
Abstract: Laser corrective surgery of the eye has become an increasingly common method for correcting vision in recent years.  The problem with current technologies in this area is that they are based on changing the shape of the cornea through material removal.  This is an inherently destructive process and either requires the removal of the epithelium (PRK) or cutting of a flap (LASIK).  Recently the Knox group has shown that it may be possible to perform noninvasive vision correction using femtosecond micromachining to alter the local index of refraction in the cornea.  This has been termed Intra-tissue Refractive Index Shaping (IRIS).  The IRIS process is dependent on energy deposition rate which is dependent on the intensity of the laser beam and the speed at which the focal spot of the beam travels through the cornea.  This leads to some interesting design problems because knowledge and control of the velocity of the focal spot of the beam becomes very important.  In this talk I will discuss the challenges involved in designing a scanning system that meets the requirements of the IRIS process as well as show my work on a possible solution.
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8/5 Summer Colloquium Speaker Annoucement

WallinWedding.pngOn Tuesday, August 5th the UR SPIE student chapter will be continuing its Summer Colloquium series with a double header! Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.

Speaker 1: Laura Kinnischtzke
What:
Interfacing Matter and Light: An Overview of Quantum Dot Spectroscopy
Abstract: Three dimensional confinement of electrons is realized in self-assembled quantum dots, and they are strong candidates for charge qubits due to the relative ease with which a single electron’s spin can be manipulated, as well as their strong optical response in the near IR.  Although each dot has a discrete spectral emission profile, the optical properties (e.g. resonance position and linewidth) vary from dot to dot. This drawback is overcome with a series of both resonant and non-resonant spectroscopic measurements using a cryogenic confocal microscope. Applying static electric and magnetic fields allows the energy landscape of the dot to be fully explored. Future experiments include optical detection of electron spin resonance in a quantum dot, which can provide clues to how a quantum dot couples to the effective magnetic field created by the nuclei of host atoms.

goodfellow_kennethSpeaker 2:
Kenny Goodfellow
What:  Integrated nanophotonics based on nanowire plasmons and atomically-thin material
Abstract:The continually increasing demands for higher speed and lower operating power devices have
resulted in the continued impetus to shrink photonic and electronic components. Atomically-thin materials, such as monolayer molybdenum disulfide (MoS2), have gained attention in this realm.  Monolayer MoS2 exhibits a direct band gap, displays large photoluminescence, and has shown promise in transistors, photodetectors, and LEDs.  I will demonstrate a primitive nanophotonic integrated circuit element composed of a single silver nanowire and single-layer MoS2 flake. I show that nanowire plasmons can excite MoS2 photoluminescence and that MoS2 excitons can decay into nanowire plasmons. I also show that the nanowire may serve the dual purpose of both exciting MoS2 photoluminescence via plasmons and recollecting the decaying exciton as nanowire plasmons.
When: 8/5/2014  11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
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7/29 Summer Colloquium Speaker Announcement

perez-romero_joseOn Tuesday, July 29th the UR SPIE student chapter will be continuing its Summer Colloquium series. Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.

Who: Jose Perez Romero
What: Design and Characterization of L3 Photonic Crystal Nanocavities with Ultra-High Quality Factors
Date: 7/29/2014
Time: 11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
Abstract: Silicon-based photonic crystal nanocavities (PCNs) have potential applications in integrated quantum photonics [1, 2], because of their ability to strongly confine light in mode volumes approaching the diffraction limit and their CMOS-compatible fabrication process [3]. It was previously thought that PCN designs with a footprint small enough for ultra-dense integration, such as L3, H1 and H0 designs, could only achieve moderately high quality factors (Q), with both theoretical and experimental values never exceeding 300,000. Recently, an optimization procedure based on genetic algorithms has completely changed the scenario, showing a dramatic improvement of the Q-values in these PCNs [4]. A joint effort between our research group and a theory group at EPFL has resulted in the successful design and fabrication of a genetically improved L3 PCN with an ultra-high Q (~ 2 million), while maintaining a very small footprint and mode volume [5]. In this talk, I will describe the design process of these so-called super-L3 PCNs, as well as their characterization in the spectral domain using cross-polarization resonant scattering spectroscopy [6] and in the time domain using cavity ring down measurements [7].
References
 
[1]   J. O’Brien, A. Furusawa, and J. Vučković, “Photonic quantum technologies,” Nature Photonics 3, 687-695 (2009).
[2]   J. Vuckovic, “Quantum optics and cavity QED with quantum dots in photonic crystals,” arXiv:1402.2541 [quant-ph] (2014).
[3]   M. Notomi, “Manipulating light with strongly modulated photonic crystals,” Reports on Progress in Physics 73, 096501 (2010).
[4]   M. Minkov and V. Savona, “Automated optimization of photonic crystal slab cavities,” Scientific Reports 4 (2014).
[5]   Y. Lai, S. Pirotta, G. Urbinati, D. Gerace, M. Minkov, V. Savona, A. Badolato, and M. Galli, “Genetically designed L3 photonic crystal nanocavities with quality factor exceeding one million,” to be published, Applied Physics Letters (June 16, 2014).
[6]   M. Galli, S. L. Portalupi, M. Belotti, L. C. Andreani, L. O’Faolain, and T. F. Krauss, “Light scattering and Fano resonances in high-Q photonic crystal nanocavities,” Applied Physics Letters 94, 071101 (2009).
[7]   T. Tanabe, M. Notomi, E. Kuramochi, A. Shinya, and H. Taniyama, “Trapping and delaying photons for one nanosecond in an ultrasmall high-Q photonic-crystal nanocavity,” Nature Photonics 1, 49-52 (2007).
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7/22 Summer Colloquium Speaker Announcement

leidner_jordanOn Tuesday, July 22nd the UR SPIE student chapter will be continuing its Summer Colloquium series with a double header! Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.

Speaker 1: Jordan Leidner
What:
Filamentation-Free Broad-Area Laser Design for Efficient Coupling to Single-Mode Fiber
Abstract:Although the quest for high-power, diffraction-limited, semiconductor lasers has arguably met with limited success, the drive for higher brightness diode lasers continues, driven by fiber laser systems.  Using tailored refractive-index and injection-current profiles, broad-area laser Beam Propagation Method simulations predict simultaneous suppression of free-carrier-induced self-focusing and far-field mode compression at high powers.  Asymmetric gain from tailored current profiles generate unconventional, null-less modes and lead to distributed gain- and loss-filtering mechanisms for increased beam quality output.  5.2-7.7W of spatiotemporally stable (filamentation-free) power enables high-efficiency (70%) coupling into SMF-28, resulting in 3.1-5.5W of fiber-coupled power for EDFA pumping with 0.72 W/A slope efficiency.  The concept is shown to be robust against the shape of the profiles, inhomogeneities in both injection current and refractive index, and thermal lensing with proper sub-mount design.

DSC06993Speaker 2:
Katelynn Sharma
What:  Measurement of spatial coherence through the shadows of small obscurations
Abstract:We present a simple method to measure the spatial coherence of a partially coherent field by analyzing measurements of the radiant intensity with and without a small, well-characterized obscuration. From these measurements, the coherence of a field can be estimated simultaneously for all pairs of points whose centroid is the same as that of the obstacle. By scanning the obstacle over the test plane, one can recover the full four-dimensional coherence function. In principle, such measurements can be performed without any refractive or diffractive elements, allowing for measurements to be done in higher frequency regimes. In the experimental results presented here, however, the radiant intensity was measured at the back-focal plane of a lens. Our results are highly consistent with theoretical predictions for obscurations whose size is on the order of the coherence width of the source.

When: 7/22/2014  11:30 am – 12:30 pmWhere: Sloan Auditorium (Goergen 101)

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7/15 Summer Colloquium Speaker Announcement

OLYMPUS DIGITAL CAMERAOn Tuesday, July 15th the UR SPIE student chapter will be continuing its Summer Colloquium series. Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.

Who: Robin Sharma
What: Two-photon fluorescence imaging of the retina in the living eye using adaptive optics
Date: 7/15/2014
Time: 11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
Abstract: Adaptive optics scanning laser ophthalmoscopy (AOSLO) permits diffraction-limited imaging of microscopic structures in the retina in living eyes. Thanks to various advances in system design and image registration software, functional imaging of different cell classes in the retina is within reach. Two-photon fluorescence imaging has a number of advantages for retinal imaging. All cells in the retina fluoresce with appropriate infrared two-photon excitation, offering the possibility of imaging every class of retinal cell, even those that are transparent in visible light. It also allows the study of molecular species whose excitation regime is in the ultraviolet, a region of the spectrum that is inaccessible in reflectance and single photon fluorescence imaging because it lies outside the transmittance spectrum of the ocular media. Additionally, it allows functional as well as structural imaging by monitoring molecular changes that are invisible with conventional imaging methods.
A two-photon adaptive optics scanning light ophthalmoscope has been developed for imaging living, anaesthetized primates. An ultrashort pulsed laser (~ 55 fs pulse-width) with a tunable central wavelength was used to excite two-photon fluorescence. Consistent with measurements made in excised retina, fluorescence emission was detected throughout the retina in vivo although the strongest autofluorescence signal originated from near the photoreceptor layer. Two-photon images of individual cells and other recognizable structures were obtained in multiple retinal layers such as the nerve fiber layer, individual rods as well as cones and retinal pigment epithelial cells. Also, the time-course of fluorescence from individual photoreceptor cells provides clues about the molecules that might be responsible for this autofluorescence. This is an important step towards noninvasively monitoring functional activity in individual retinal layers.
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7/8 Summer Colloquium Speaker Announcement

head_stephenOn Tuesday, July 8st the UR SPIE student chapter will be continuing its Summer Colloquium series. Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.

Who: Steve Head
What: Arbitrary Spatially-Varying Polarization State Generator for Deep Sub-Wavelength Metrology​
Date: 7/8/2014
Time: 11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
Abstract: The lithography industry makes use of a wide array of tools for metrology of their nano-scale structures.  Scatterometry is one such method in which the scattered light from a periodic test structure is compared with theoretical results from Rigorous Coupled Wave Analysis in order to back-out structure parameters such as critical dimension, film thicknesses, and sidewall angle.  Current scatterometry methods could possibly be improved by using a focused beam to acquire angular scatter information in a single measurement and by tailoring the input polarization to make the output more sensitive to small deviations.  This talk will focus on the polarization generator I helped build and how it can be used to maximize the ability of a scatterometry system to back-out structure parameters.
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7/1 Summer Colloquium Speaker Announcement

picOn Tuesday, July 1st the UR SPIE student chapter will be continuing its Summer Colloquium series. Please bring your lunch and come listen to our next presentation! Snacks and beverages will be provided.
Who: Patrice Tankam
What: Multiple-Wavelength Digital Holography and Applications
Date: 7/1/2014
Time: 11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
Abstract: Since its discovery in 1947 by Denis Gabor, Holography was shown to be a powerful tool to perform “real” 3D imaging and optical metrology. The development of high-resolution CCDs and powerful processors during the last decades opened new opportunities to apply digital holography in different domains. Digital holography combines the interferometric recording of the light scattered from the object and the back-propagation computation of the interference pattern to retrieve the 3D information of the object. Most of the recent developments and accomplishments in digital holography were based on a single-wavelength configuration. However, a multiple-wavelength is necessary to obtain the true color of the object or the absolute value of the measurement. This presentation will focus on my contribution in multiple-wavelength digital holography applied in several projects (aerodynamic flow visualization, mechanics, electronics, etc).

 

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6/24 Summer Colloquium Speaker Announcement

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On Tuesday June 24th, the UR SPIE student chapter will be kicking off its annual Summer Colloquium series. Because this is the kickoff of the colloquium series, we will be providing FREE PIZZA in addition to other snacks and refreshments!
Who: Dustin Shipp
What: Precise, time-lapsed measurements of organelle sizes in single cells by Holographic Angular Domain Elastic Scattering (HADES)
Date: 6/24/2014
Time: 11:30 am – 12:30 pm
Where: Sloan Auditorium (Goergen 101)
Abstract: We demonstrate a label-free method of simultaneously measuring chemical and structural changes in a single cell over time. Raman spectroscopy obtains chemical information. Angular scattering allows estimates of organelle sizes. Previously, organelle size estimates in single cells were unstable due to the effects of speckle. The small illuminated field causes speckle to affect measurements of single cells more than measurements of many cells or bulk tissue. These speckle effects have been overcome through holographic angular domain elastic scattering (HADES), which records a complex scattered field that can be numerically propagated to any plane. In the image plane, we apply a series of virtual diffusers that reduce the coherence between different intracellular scatterers. Such diffusers are most easily created in silico, necessitating manipulation of the full complex field. By reducing the coherence between scatterers, HADES is able to reduce the effects of speckle and obtain stable organelle size estimates from single cells. To demonstrate the effectiveness of HADES on a biological system, we induce mitochondrial swelling and measure the organelle sizes of single cells over the next several hours. HADES and Raman spectroscopy are both well-suited to study a variety of changes in single cells over time. Prospective cellular systems for study by these methods will be discussed.
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FARO Technologies – 9/13/13

faroOn Friday, September 13th, a representative from FARO Technologies will be present.  Please join us for a lunchtime session featuring a company presentation, product demos, and, of course, free pizza.  See below for more details.

Speaker:  Michelle C. Edwards
Title:  Optical Technology in Imaging and Portable Coordinate Metrology – Bringing the Real World to the Virtual World.
Abstract: FARO the world’s most trusted source for 3D measurement technology, develops and markets computer-aided measurement and imaging devices and software. Technology from FARO permits high-precision 3D measurement, imaging and comparison of parts and complex structures within production and quality assurance processes. The devices employ varied technologies, and are applied to compare real world parts to engineering design data in industries such as aerospace and automotive; The devices also capture the as-built state of objects and define them in the virtual world to allow for duplication, modification, or documentation of the data needed in industries. This session will present the technology, and allow opportunity for hands on experience with a laser tracker, laser scanner, and Scan arm.

Venue: Goergen 108
Date: 9/13/13
Time: Noon – 2 pm

Speaker Bio: Michelle Edwards is the Applications Engineering Manager for the Americas Region, at FARO Technologies Inc, the leading provider of 3D laser measurement tools.  Michelle has worked for FARO Technologies since 2003. She leads a team of 28 engineers, who are in the field supporting the firm’s clients, account managers and distributors in the sales, installation and training processes.  Michelle is also accountable for the recruitment of engineers for her team.    At FARO, Michelle has been a part of projects in support of customers including GE Energy, the US Army, NASA, Lockheed-Martin, Boeing, Hyundai and hundreds of other initiatives.   The type of projects have included  development of inspection routines, customization of training programs, and adapting new technology to enable modifications and upgrades of aircraft & vehicles onsite instead of transporting them.

Prior to joining FARO, Michelle was a business owner in the hospitality industry operating a franchised hotel and restaurant.  In her business, she led the initiative to ensure guests, corporations, and neighboring businesses all communicated to achieve the highest level of satisfaction for customers.

Michelle received a BS in Aerospace Engineering from the Embry Riddle Aeronautical University.  She lives with her husband and two children in Ormond Beach, FL.

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