Statistics and Probability Seminars

OSA/SPIE, SPRC and Ginzton Lab present "Frequency comb-based nonlinear spectroscopy"

Topic: 
Frequency comb-based nonlinear spectroscopy
Abstract / Description: 

Rapid and precise measurements are and always have been of interest in science and technology partly because of their numerous practical applications. Since their development, frequency comb-based methods have revolutionized optical measurements. They simultaneously provide high resolution, high sensitivity, and rapid acquisition times. These methods are being developed for use in many fields, from atomic and molecular spectroscopy, to precision metrology, to spectral LIDAR and even atmospheric monitoring. However they cannot address the issues of inhomogeneously broadened transitions or sample heterogeneity. This is especially important for remote chemical sensing applications.

In this talk I will discuss a novel optical method, that I recently developed, which overcomes these limitations. I will demonstrate its capabilities for probing extremely weak fundamental processes as well as its applications for rapid and high resolution chemical sensing.

 

References:

B. Lomsadze, B. Smith and S. T. Cundiff. "Tri-comb spectroscopy". Nature Photonics 12, 676, 2018.
B. Lomsadze and S. T. Cundiff. "Frequency-comb based double-quantum two-dimensional spectrum identifies collective hyperfine resonances in atomic vapor induced by dipole-dipole interactions." Physical Review Letters 120, 233401, 2018.
B. Lomsadze and S. T. Cundiff. "Frequency combs enable rapid and high-resolution multidimensional coherent spectroscopy". Science 357, 1389, 2017
B. Lomsadze and S. T. Cundiff. "Frequency comb-based four-wave-mixing spectroscopy". Optics letters 42, 2346, 2017

Date and Time: 
Wednesday, June 12, 2019 - 4:15pm
Venue: 
Allen 101X

RESCHEDULED: OSA/SPIE, SPRC and Ginzton Lab present "Frequency comb-based nonlinear spectroscopy"

Topic: 
RESCHEDULED: Frequency comb-based nonlinear spectroscopy: Bridging the gap between fundamental science and cutting-edge technology
Abstract / Description: 

RESCHEDULED for June 12

Rapid and precise measurements are and always have been of interest in science and technology partly because of their numerous practical applications. Since their development, frequency comb-based methods have revolutionized optical measurements. They simultaneously provide high resolution, high sensitivity, and rapid acquisition times. These methods are being developed for use in many fields, from atomic and molecular spectroscopy, to precision metrology, to spectral LIDAR and even atmospheric monitoring. However they cannot address the issues of inhomogeneously broadened transitions or sample heterogeneity. This is especially important for remote chemical sensing applications.

In this talk I will discuss a novel optical method, that I recently developed, which overcomes these limitations. I will demonstrate its capabilities for probing extremely weak fundamental processes as well as its applications for rapid and high resolution chemical sensing.

 

References:

B. Lomsadze, B. Smith and S. T. Cundiff. "Tri-comb spectroscopy". Nature Photonics 12, 676, 2018.
B. Lomsadze and S. T. Cundiff. "Frequency-comb based double-quantum two-dimensional spectrum identifies collective hyperfine resonances in atomic vapor induced by dipole-dipole interactions." Physical Review Letters 120, 233401, 2018.
B. Lomsadze and S. T. Cundiff. "Frequency combs enable rapid and high-resolution multidimensional coherent spectroscopy". Science 357, 1389, 2017
B. Lomsadze and S. T. Cundiff. "Frequency comb-based four-wave-mixing spectroscopy". Optics letters 42, 2346, 2017

Date and Time: 
Wednesday, March 20, 2019 - 4:15pm
Venue: 
Allen 101X

John G. Linvill Distinguished Seminar on Electronic Systems Technology

Topic: 
Internet of Things and Internet of Energy for Connecting at Any Time and Any Place
Abstract / Description: 

In this presentation, I would like to discuss with you how to establish a sustainable and smart society through the internet of energy for connecting at any time and any place. I suspect that you have heard the phrase, "Internet of Energy" less often. The meaning of this phrase is simple. Because of a ubiquitous energy transmission system, you do not need to worry about a shortage of electric power. One of the most important items for establishing a sustainable society is [...]


"Inaugural Linvill Distinguished Seminar on Electronic Systems Technology," EE News, July 2018

 

Date and Time: 
Monday, January 14, 2019 - 4:30pm
Venue: 
Hewlett 200

Statistics Seminar: Inference, Computation, and Visualization for Convex Clustering and Biclustering

Topic: 
Inference, Computation, and Visualization for Convex Clustering and Biclustering
Abstract / Description: 

Hierarchical clustering enjoys wide popularity because of its fast computation, ease of interpretation, and appealing visualizations via the dendogram and cluster heatmap. Recently, several have proposed and studied convex clustering and biclustering which, similar in spirit to hierarchical clustering, achieve cluster merges via convex fusion penalties. While these techniques enjoy superior statistical performance, they suffer from slower computation and are not generally conducive to representation as a dendogram. In the first part of the talk, we present new convex (bi)clustering methods and fast algorithms that inherit all of the advantages of hierarchical clustering. Specifically, we develop a new fast approximation and variation of the convex (bi)clustering solution path that can be represented as a dendogram or cluster heatmap. Also, as one tuning parameter indexes the sequence of convex (bi)clustering solutions, we can use these to develop interactive and dynamic visualization strategies that allow one to watch data form groups as the tuning parameter varies. In the second part of this talk, we consider how to conduct inference for convex clustering solutions that addresses questions like: Are there clusters in my data set? Or, should two clusters be merged into one? To achieve this, we develop a new geometric representation of Hotelling's T2-test that allows us to use the selective inference paradigm to test multivariate hypotheses for the first time. We can use this approach to test hypotheses and calculate confidence ellipsoids on the cluster means resulting from convex clustering. We apply these techniques to examples from text mining and cancer genomics.

This is joint work with John Nagorski and Frederick Campbell.


The Statistics Seminars for Winter Quarter will be held in Room 380Y of the Sloan Mathematics Center in the Main Quad at 4:30pm on Tuesdays. 

Date and Time: 
Tuesday, March 13, 2018 - 4:30pm
Venue: 
Sloan Mathematics Building, Room 380Y

Statistics Seminar: Understanding rare events in models of statistical mechanics

Topic: 
Understanding rare events in models of statistical mechanics
Abstract / Description: 

Statistical mechanics models are ubiquitous at the interface of probability theory, information theory, and inference problems in high dimensions. To develop a refined understanding of such models, one often needs to study not only typical fluctuation theory but also the realm of atypical events. In this talk, we will focus on sparse networks and polymer models on lattices. In particular we will consider the rare events that a sparse random network has an atypical number of certain local structures, and that a polymer in random media has atypical weight. The random geometry associated with typical instances of these rare events is an important topic of inquiry: this geometry can involve merely local structures, or more global ones. We will discuss recent solutions to certain longstanding questions and connections to stochastic block models, exponential random graphs, eigenvalues of random matrices, and fundamental growth models.

Date and Time: 
Tuesday, January 30, 2018 - 4:30pm
Venue: 
Sloan Mathematics Building, Room 380Y

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