Professor, Physics Department, University of Colorado
Noel Clark received his Ph.D. in Physics from MIT in 1970. He subsequently
held the positions of Research Fellow and Assistant Professor of Applied
Physics at Harvard, before moving to the University of Colorado in 1977.
Research in Professor Clark's group is directed toward understanding
and using the properties of condensed phases, ranging from experiments
on the fundamental physics of phase transitions, such as melting, to
the development of liquid crystal electro-optic light valves. The
primary experimental tools are laser light scattering, electrooptics,
video microscopy and high resolution synchrotron X-ray scattering. Much
of the research is on the physics of liquid crystals, phases of matter
having structure intermediate to that of liquids and solids, and on the
physics of colloids, suspensions of one material in another that
exhibit order on large length scales. These materials have become
important testing grounds for modern theories of phase transitions,
which is the principal focus of research. The group recently made a
fundamental discovery about the nature of the melting transition,
showing it to be a condensation of "broken bonds."
Applied research is in the area of liquid crystal electro-optics. Professor
Clark's group has pioneered a major new liquid crystal electro-optic technology,
employing ferroelectric liquid crystals to make high-speed bistable light
valves. These devices, which can be configured into linear and matrix arrays,
are of particular use in optical computing and are one of the principal
technologies to be developed in the Center for Optoelectronic Computing
Systems at the University of Colorado.
Recently the group has begun a new project on fabrication of structures
on a nanometer length scale. This work, which grew out of their research
on biomembrane liquid crystals, is directed toward using two-dimensional
protein crystals as fabrication masks and templates.
- "Diastereomeric liquid crystal domains at the mesoscale," D. Chen, M. Tuchband, B. Horanyi, E. Korblova, D. M. Walba, M. A. Glaser, J. E. Maclennan, and N. A. Clark, Nature Communications 6, 7763 [10 pages] (2015). DOI: 10.1038/ncomms8763
- "Mutual Diffusion of Inclusions in Freely Suspended Smectic Liquid Crystal Films," Z. Qi, Z. H. Nguyen, C. S. Park, M. A. Glaser, J. E. Maclennan, N. A. Clark, T. Kuriabova, and T. R. Powers, Physical Review Letters 113 (12), 128304 [5 pages] (2014).
- "Chiral heliconical ground state of nanoscale pitch in a nematic liquid crystal of achiral molecular dimers," D. Chen, J. H. Porada, J. B. Hooper, A. Klittnick, Y. Shen, M. R. Tuchband, E. Korblova, D. Bedrov, D. M. Walba, M. A. Glaser, J. E. Maclennan, and N. A. Clark, PNAS 110 (40), 15931–15936 (2013). DOI:10.1073/pnas.1314654110
- "Nanoconfinement of guest materials by helical nanofilament networks of bent-core mesogens," D. Chen, C. Zhu, H. Wang, J. E. Maclennan, M. A. Glaser, E. Korblova, D. M. Walba, J. A. Rego, E. A. Soto-Bustamante, and N. A. Clark, Soft Matter 9, 462–471 (2013).
- "Athermal photofluidization of glasses," G. J. Fang, J. E. Maclennan, Y. Yi, M. A. Glaser, M. Farrow, E. Korblova, D. M. Walba, T. E. Furtak, and N. A. Clark, Nature Communications 4, 1521 [10 pages] (2013). DOI: 10.1038/ncomms2483
- "Spontaneous Fluid Ferroelectric Order in a Bent-Core Liquid Crystal of Orthorhombic Smectic Layers," R. A. Reddy, C. Zhu, R. Shao, E. Korblova, T. Gong, Y. Shen, E. Garcia, M. A. Glaser, J. E. Maclennan, D. M. Walba, and N. A. Clark, Science 332, 72–77 (2011).
- "Chiral Isotropic Liquids from Achiral Molecules," L. E. Hough, M. Spannuth, M. Nakata, D. A. Coleman, C. D. Jones, G. Dantlgraber, C. Tschierske, J. Watanabe, E. Körblova, D. M. Walba, J. E. Maclennan, M. A. Glaser, N. A. Clark, Science 25 , 452–456 (2009).
- "Organization of liquid crystals on submicron scale topographic patterns with fourfold symmetry prepared by thiolene photopolymerization-based nanoimprint lithography," Y. W. Yi, V. Khire, C. N. Bowman, J. E. Maclennan, and N. A. Clark, Journal of Applied Physics 103, 093518 (2008).
- "Electric-Field-Driven Deracemization," A. Kane, R.-F. Shao, J. E. Maclennan, L. Wang, D. M. Walba, and N. A. Clark, ChemPhysChem 8 , 170 – 174 (2007).
- "Direct Measurement of Interaction Forces between Islands on Freely Suspended Smectic C Films using Multiple Optical Tweezers," A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, Ferroelectrics 344 , 71 (2006); also in www.e-lc.org .
- "Electric Field Induced Chirality Flipping in Smectic Liquid Crystals," M. Nakata, R.-F. Shao, J. E. Maclennan, W. Weissflog, and N. A. Clark, Physical Review Letters 96 , 067802 (2006).
- "Polarization-Modulated Smectic Liquid Crystal Phases," D. A. Coleman, J. Fernsler, N.Chattham, M. Nakata, Y. Takanishi, E. Korblova, D. R.Link, R.-F.Shao, W.G. Jang, J. E. Maclennan, O. Mondain-Monval, C. Boyer, W. Weissflog, G. Pelzl, L.-C. Chien, J. Zasadzinski, J. Watanabe, D. M. Walba, H. Takezoe, and N. A. Clark, Science 301 , 1204-1211 (2003).
- "Control of Molecular Orientation in Electrostatically Stabilized Ferroelectric Liquid Crystals," D. Coleman, D. Mueller, N. A. Clark, J. E. Maclennan, R.-F. Shao, S. Bardon, and D. M. Walba, Physical Review Letters 91 , 175505 (2003).
- "Spontaneous Formation of Horizontal Chevrons in Smectic-C* Liquid Crystals," G. Strangi, D. A. Coleman, J. E. Maclennan, M. Copic, and N. A. Clark, Applied Physics Letters 78 , 1532 (2001).
- "A Ferroelectric Liquid Crystal Conglomerate Composed of Racemic Molecules," D. M. Walba, E. Körblova, R. Shao, J. E. Maclennan, D. R. Link, M. A. Glaser, and N. A. Clark, Science 288 , 2181 (2000).
- "Spontaneous Formation of Polar Chiral Layers from Achiral Molecules in a Novel Antiferroelectric Liquid Crystal Phase," D. R. Link, G. Natale, R. Shao, J. E. Maclennan, N. A. Clark, E. Korblova, and D. M. Walba, Science 278, 1924-1927 (1997).