Approaching Piezoelectric Terahertz Acoustics

Friday, March 13, 2026, 4:00 p.m. Central Time

Jack P. Kramer
Chandra Family Department of Electrical and Computer Engineering
The University of Texas at Austin
https://www.ece.utexas.edu/

Piezoelectric acoustic resonators are critical building blocks for modern cellular communication systems, where they compose radio frequency filters. Despite widespread adoption below 6 GHz, scaling these devices to frequencies exceeding 10 GHz has proved challenging due to material and design limitations. These limits hinder the electrical to mechanical coupling and resonator quality factors, both critical metrics for RF filters. In this talk, we will discuss how so-called periodically poled piezoelectric films help to address these challenges and have enabled acoustic resonators from tens of GHz to above 100 GHz, into the sub-THz. We will discuss how these advancements have enabled tens of GHz filters that could be critical components as modern communication systems push to higher frequencies. We will also highlight some emerging challenges that these resonators face as the acoustic wavelengths approach the spacing of tens of atoms.

The Development of the Túngara Frog Larynx and the Sounds it Produces: Shut Up and Grow Up

Friday, February 27, 2026, 4:00 p.m. Central Time

Professor Michael J. Ryan
Department of Integrative Biology
The University of Texas at Austin
and
Smithsonian Tropical Research Institute
Gamboa, Panama
https://sites.utexas.edu/the-ryan-lab/

Most species of frogs rely on loud and conspicuous mating calls used by males to attract females for the purpose of mating. We understand many aspects of this communication system: its role in speciation and sexual selection; how the environment does or does not influence its evolution; and how the auditory system decodes and perceives this acoustic signal. Less is known about the function and development of the voice production system, especially the larynx. We describe the ontogeny of laryngeal morphology in both sexes, use ablation experiments and bound graph models to understand its inner workings, and identify a zone of silence in which males could call but they don’t. Ongoing studies ask why this is so.

On the Spectral Homogenization of Wave Motion in Periodic Continua and Origami-Inspired Structures

Friday, February 20, 2026, 4:00 p.m. Central Time

Professor Othman Oudghiri-Idrissi
Fariborz Maseeh Department of Civil, Architectural, and Environmental Engineering
The University of Texas at Austin
https://caee.utexas.edu/person/othman-oudghiri-idrissi/

We establish a comprehensive analytical framework for dynamic homogenization of wave motion at arbitrary frequency in (i) perforated periodic continua and (ii) origami-inspired periodic structures modeled using a bar-and-hinge paradigm. For a prescribed spectral content of an applied body force, the activated Bloch eigenstates are identified and classified according to the multiplicity of the participating energy levels. Near an isolated dispersion surface, projection onto the dominant Bloch mode yields an effective field equation with a homogenized source term, providing leading- and second-order approximations of both macroscopic (mean) and microscopic wave motion. When multiple dispersion surfaces are activated, coupled zeroth- and first-order effective systems are derived, accommodating spectral configurations including Dirac points, avoided crossings, and near-degenerate clusters. In the absence of forcing, the resulting formulation reduces to a low-order algebraic eigenvalue problem that accurately captures the local geometry of clustered dispersion branches. The framework is validated by comparing asymptotic dispersion predictions with direct numerical simulations and is applied to two-dimensional Kagome lattices with Neumann exclusions, square lattices with Dirichlet obstacles, Miura-ori sheets, and one-dimensional Miura tubes. Results demonstrate accurate approximation of both dispersion characteristics and body-force-induced waveforms, resolving effective and microstructural dynamics with comparable fidelity.

4D Metamaterials: From Spatial to Temporal Wave Control

Friday, February 13, 2026, 4:00 p.m. Central Time

Professor Emanuele Galiffi
Chandra Family Department of Electrical and Computer Engineering
The University of Texas at Austin
https://www.emanuelegaliffi.me/

Metamaterials enable wave manipulation beyond the limits of natural materials by exploiting subwavelength spatial structuring, leading to a host of exotic wave behaviors ranging from negative refraction to cloaking, as well as applications ranging from the extreme miniaturization of optical components to nonreciprocal wave propagation. More recently, the metamaterials community has started exploring the opportunity of generalizing this paradigm to the temporal dimension, opening a new research front on 4D metamaterials. Intriguingly, causality results in time behaving as a different sort of dimension than its spatial counterparts, leading to the manipulation of the energy and frequency of waves, rather than their momentum and wave vector, resulting in a variety of opportunities for extreme wave control ranging from new amplification paradigms to unidirectional wave propagation and gain, and enabling the breaking of the conventional limitations of passive media, such as the Rozanov and Chu bandwidth for absorbers and antennas. In this talk I will provide an overview of the rising field of time-varying metamaterials, focusing on their capabilities in manipulating the energy and frequency content of waves, and how the engineering of their coherent illumination input can dramatically control our ability to exploit them to produce gain, loss and perfect frequency conversion.

The Sounds of an Ocean Eddy

Friday, January 30, 2026, 4:00 p.m. Central Time

Dr. Robert T. Taylor
Applied Research Laboratories
The University of Texas at Austin
https://www.arlut.utexas.edu/

Northern latitude ocean environments are dynamic and complex, with shortened spatial and temporal scales leading to dramatic changes in water column structure compared to more equatorial regimes. In the waters surrounding Jan Mayen Island in the Nordic Seas, eddies frequently spin off of the Norwegian Atlantic Current, further complicating the local ocean state and the associated acoustic propagation environment. The Northern Ocean Rapid Surface Evolution (NORSE) experiment, conducted between 2022 and 2023, sought to understand both the internal ocean dynamics and the corresponding impact on the underwater acoustic environment. A year-long collection of water column temperature, salinity, and flow velocity, were obtained with a suite of sensors mounted on a mooring line located on a 420 m deep ridge near Jan Mayen. To study the acoustics, ARL:UT deployed a 380 m long vertical line array mooring roughly 1 km away, providing ambient sound measurements throughout the water column. This presentation details the investigation of various acoustic sources of opportunity and their relationship to the in situ ocean environment. Inversion techniques were developed to enable continuous acoustic estimates of temperature, flow speed, and flow direction. In particular, the acoustic data reveal the passage of an anti-cyclonic eddy directly over the ridge during a two-week period. This work shows that hydrophone arrays can be used simultaneously for both ocean parameter estimation and conventional acoustic applications.

Mastering, Consulting, and Education: One Perspective on a Career in Professional Audio

Friday, January 23, 2026, 4:00 p.m. Central Time

Nick Landis
Chief Mastering Engineer
Nick Landis LLC
Austin, TX
www.nicklandis.com

What does a career in professional audio really look like? In this seminar, Nick Landis will share his journey as a mastering engineer, acoustics consultant, and educator. He will discuss his approach to projects, how he differentiates himself in a competitive market, and how his workflow has evolved over the years with new technologies. Nick will also reflect on career flow beyond mastering, including consulting on broad acoustics challenges—often collaborating with architects or guiding DIY solutions—and his experiences teaching audio production and acoustics at Austin Community College.  The talk will highlight how multiple facets of professional audio including creative process, technical problem-solving, client collaboration, and education intersect to create a sustainable career. Nick will also touch on his involvement with The Recording Academy and the Audio Engineering Society, providing perspective on professional engagement in the field. The seminar will be conversational and story-driven, with a generous Q&A session designed to foster discussion about mastering, acoustics consulting, and career development in audio.