About

Irmgard Bischofberger is an Associate Professor of Mechanical Engineering at the Massachusetts Institute of Technology. Her research interests include pattern formation, fluid dynamics, and soft condensed matter. She holds a Master of Science and a Ph.D. from the University of Fribourg, Switzerland, obtained in 2006 and 2011 respectively. Bischofberger has received numerous honors, including the Gallery of Soft Matter Award at the APS March Meeting in 2023 and 2022, the Junior Bose Award for Teaching Excellence at MIT in 2022, and the Ruth and Joel Spira Award for Distinguished Teaching in 2020. Her professional memberships include the American Physical Society, the American Institute of Chemical Engineers, the American Chemical Society, and the Society of Rheology. She is actively involved in professional service and contributes to the academic community through her research and teaching at MIT.

Research topics

• Condensed matter physics
• Physics
• Mathematics
• Thermodynamics
• Physical chemistry
• Classical mechanics
• Chemistry
• Mechanics
• Statistical physics
• Quantum mechanics
• Chemical physics

Selected publications

• Data published in research paper: https://doi.org/10.1039/d5sm00990a

  Open MIND · 2026-02-26

  datasetSenior author

  We show that filler-hydrogel composites exhibit viscoelastc properties with signatures of successive transitions from linear to non-linear elasticity to macroscopic irreversibility with increasing strain amplitude.

  DOI

• Delamination and out-of-plane deformation in drying colloidal suspensions

  Soft Matter · 2026-01-01

  articleOpen accessSenior author

  A drop of a colloidal suspension placed on a substrate forms a solid particle deposit as it dries. As water evaporates, large gradients in pore pressure inside the porous deposit cause shrinkage and stresses. The deposit cracks, then delaminates from the substrate, and bends out of plane, creating a striking three-dimensional structure. Previous models have attributed the out-of-plane deformation to pore pressure gradients through the deposit's thickness, a hypothesis our findings contradict. Through a combination of interference and confocal microscopy, we show that the final curvature strongly depends on the deposit thickness, with thinner deposits curving more. We propose a mechanism where the curvature is driven not by vertical pressure gradients, but by much larger radial pressure gradients across the length of the deposit. The resulting in-plane differential shrinkage creates geometric frustration that is resolved through out-of-plane buckling. We validate this mechanism using non-Euclidean plate simulations, which successfully reproduce the buckling behavior and the observed dependence of curvature on thickness.

  PublisherDOI

• Data published in research paper: https://doi.org/10.1039/d5sm00990a

  Figshare · 2026-02-26

  datasetOpen accessSenior author

  We show that filler-hydrogel composites exhibit viscoelastc properties with signatures of successive transitions from linear to non-linear elasticity to macroscopic irreversibility with increasing strain amplitude.

  PublisherDOI

• Author response for "Nonlinear elasticity and transition to macroscopic irreversibility in composite hydrogels"

  2026-02-08

  peer-reviewSenior author
  PublisherDOI

• Nonlinear elasticity and transition to macroscopic irreversibility in composite hydrogels

  Soft Matter · 2026-01-01

  articleOpen accessSenior authorCorresponding

  ' reaches its maximum, characterized by a marked change in the stress relaxation dynamics. Beyond , the composites no longer recover their initial viscoelastic properties in repeated strain amplitude sweeps, indicating that the material has sustained macroscopically irreversible changes and a permanent loss of elasticity. We thus identify three distinct regimes in the strain-stiffening materials: nonlinear elasticity, macroscopic irreversibility, and yielding. We further suggest that the plasticity underpinning macroscopic irreversibility is due to the breaking of bonds that contribute most to the composite's strain stiffening response in the hydrogel matrix.

  PublisherOA PDFDOI

• Pattern Formation and Instabilities in Particulate Suspensions

  Annual Review of Fluid Mechanics · 2025-10-01 · 2 citations

  articleOpen accessSenior author

  Particulate suspensions, consisting of solid particles dispersed in a fluid, exhibit complex flow behaviors influenced by multiple factors, including particle interactions, concentration gradients, and external forces. Suspensions play an important role in diverse processes, from sediment transport to food processing, and display instabilities triggered by shear-driven effects, frictional interactions, and viscous forces. These instabilities can often be understood by identifying the key mechanical quantities that govern the dynamics. Following hydrodynamic tradition, such mechanics can be characterized by dimensionless numbers, which encapsulate the interplay between geometric, kinematic, and mechanical factors. Many of these numbers represent competitions between opposing pairs of mechanical quantities, which we discuss in detail while also considering a few phenomena that require more complex combinations. By emphasizing the underlying mechanical principles, this review provides a perspective for understanding pattern formation and flow instabilities in confined particulate suspensions across different flow geometries.

  PublisherDOI

• Video: Fractured Flows: Bursting Bubbles in Dense Suspensions

  2025-11-23

  articleOpen accessSenior author
  PublisherDOI

• Author response for "Nonlinear elasticity and transition to macroscopic irreversibility in composite hydrogels"

  2025-12-27

  peer-reviewSenior author
  PublisherDOI

• Poster: Interfacial Intricacies: Phase Transitions in Liquid Crystals

  2025-11-23

  articleOpen accessSenior author
  PublisherDOI

• Permeability–selectivity trade-off for a universal leaky channel inspired by mobula filters

  Proceedings of the National Academy of Sciences · 2024-11-25 · 2 citations

  articleOpen access

  Mobula rays have evolved leaf-shaped filter structures to separate food particles from seawater, which function similarly to industrial cross-flow filters. Unlike cross-flow filtration, where permeability and selectivity are rationally designed following trade-off analyses, the driving forces underlying the evolution of mobula filter geometry have remained elusive. To bridge the principles of cross-flow and mobula filtration, we establish a universal framework for the permeability-selectivity trade-off in a leaky channel inspired by mobula filters, where permeability and selectivity are characterized by the pore-scale leaking rate and the cut-off particle size, respectively. Beyond the classic pore-flow regime in cross-flow filtration, we reveal transition and vortex regimes pertinent to mobula filtration. Combining theory, physical experiments, and simulations, we present distinct features of water permeability and particle selectivity across the three regimes. In particular, we identify an unreported 1/2-scaling law for the leaking rate in the vortex regime. We conclude by demonstrating that mobula filters strike an elegant balance between permeability and selectivity, which enables mobula rays to simultaneously satisfy biological requirements for breathing and filter feeding. By integrating cross-flow and mobula filtration into a universal framework, our findings provide fundamental insights into the physical constraints and evolutionary pressures associated with biological filtration geometries and lay the foundation for developing mobula-inspired filtration in industry.

  PublisherDOI

Frequent coauthors

• Sidney R. Nagel

  University of Chicago

  34 shared

• Rui Zhang

  Northwest Institute For Non-Ferrous Metal Research

  14 shared

• Gareth H. McKinley

  14 shared

• Paul Lilin

  Massachusetts Institute of Technology

  11 shared

• Véronique Trappe

  10 shared

• Qing Zhang

  Computational Physics (United States)

  10 shared

• Shuang Zhou

  Ningbo University of Technology

  10 shared

• Bahni Ray

  Indian Institute of Technology Delhi

  8 shared

Labs

• MIT Department of Mechanical EngineeringPI

Awards & honors

• Gallery of Soft Matter Award, APS March Meeting (2023)
• Junior Bose Award for Teaching Excellence, MIT (2022)
• Gallery of Soft Matter Award, APS March Meeting (2022)
• Committed to Caring Award, MIT Office of Graduate Education…
• Milton van Dyke Award Winner, Gallery of Fluid Motion, APS D…