Biography

Erik Lascaris is a Postdoctoral Associate and Physics Lecturer at Boston University. After receiving his engineering degree in Applied Physics from the University of Twente, Netherlands in 2006, he continued his studies at Boston University where in 2014 he received his Physics Ph.D. for his studies on Liquid-Liquid Phase Transitions. Being a valued teacher as well as researcher, Boston University awarded him with both a Lecturer position in addition to a Postdoctoral Associate research position. His research is a continuation and expansion of his Ph.D. studies, focusing on the rich field of fluid behavior on the molecular level.




Research

Although my interests are extremely broad, they all share a common question: How can one use computer simulations to accurately predict the behavior of a system? The systems I mainly focus on are those on a molecular level, and therefore the Molecular Dynamics (MD) method has often been my method of choice. A related question is How can we model a system accurately, using data obtained at higher spacial resolution and/or higher time resolution?. For instance, methods such as coarse-graining and mult-scale physics.

Several of the projects I have been working on are listed below.


Liquid-liquid phase transitions, in water and other tetrahedral liquids

Project in collaboration with Arizona State University, Princeton University, University of Houston, and many others.

We employ computer simulations and statistical physics to understand the origin of liquid-liquid phase transitions and their relationship with anomalies typical of liquid water. Compared with other liquids, water has many anomalies. For example the density anomaly: when water is cooled below 4 C the density decreases rather than increases. This and other anomalies have also been found to occur in a few other one component liquids, sometimes in conjunction with the existence of a liquid-liquid phase transition (LLPT) between a low-density liquid (LDL) and a high-density liquid (HDL). Using simple models we explain how these anomalies arise from the presence of two competing length scales. As a specific example we investigate the cut ramp potential, where we show the importance of "competition" in this context, and how one length scale can sometimes be zero. When there is a clear energetic preference for either LDL or HDL for all pressures and temperatures, then there is insufficient competition between the two liquid structures and no anomalies occur. From the simple models it also follows that anomalies can occur without the presence of a LLPT and vice versa. It remains therefore unclear if water has a LLPT that ends in a liquid-liquid critical point (LLCP), a hypothesis that was first proposed based on simulations of the ST2 water model.

Previous research has indicated the possible existence of a LLCP in liquid silica. We have performed a detailed analysis of two different silica models (WAC and BKS) at temperatures much lower than was previously simulated. Within the accessible temperature range we found no LLCP in either model, although in the case of WAC potential it is closely approached. We compare our results with those obtained for other tetrahedral liquids and conclude that insufficient "stiffness" in the Si-O-Si bond angle might be responsible for the absence of a LLCP. goal? - LLCP in water and other liquids


Bio-plastics

Project in collaboration with MHG Biopolymers

Paper is easy to recycle (and is biodegradable), but paper products are often hard to recycle because of the polyethylene coating. Biodegradable plastics and bio-sourced products from polyhydroxyalkanoates (PHA) and polylactide (PLA) can be used to develop a more environmentally friendly coating. A bio-friendly coating would reduce the number of trees necessary for the same amount of paper because more can be recycled. In addition, the paper products with bio-friendly coating can be composted and thus used to grow new trees.

PHAs are polyesters with various-length side chains that can be methyl, ethyl, or propyl groups. Each polymer molecule consists of repeating units whose structure is determined by the bacterial strain and carbon feedstock. All repeat units have the same stereochemical, three-dimensional configuration as a result of the biosynthetic enzymes that assemble the polymer. This configuration determines some of the physical properties of the polymer, such as crystallinity and glass transition temperature, along with the activities of enzymes involved in biosynthesis and biodegradation.

Molecular Dynamics (MD) simulations can be used to determine the types of additives that would improve the solubility of the bio-polymers. Solubility is a molecular-level problem, and hence MD is a great tool to understand the mechanisms involved.


Visco-elastic surfactants

Project in collaboration with Schlumberger-Doll Research

Aqueous fluids of polymers and amphiphiles are commonly used in fracturing applications to increase the viscosity of the fracking fluids to allow them to carry large amounts of sand or proppants. Traditional polymer-based fracking fluids work well but can leave behind residue, leading to a reduction of fracture permeability and the buildup of filter cake. Visco-elastic surfactants (VES) may provide a better alternative, as these fluids obtain their rheological properties via the entanglement of worm-shaped micelles and produce little residue after fracturing. However, although VES systems provide simple operation, they are ideal fluids only in low-temperatures wells because of their poor high-temperature stability.

For reasons of safety, cost, and complexity, laboratory research done on VES fluids is often limited to temperatures below 100 C and ambient pressure. The behavior of these fluids at downhole conditions is thus poorly understood, which could result in an over- or under-engineering of fluids for fracturing applications. Computer simulations such as the Molecular Dynamics method can help to understand and predict properties of these water-amphiphile systems at downhole conditions.




Teaching

Docendo discimus, "by teaching, we learn".


Current courses:

PY106 Elementary Physics 2, Fall 2017 (4 credits)
Elementary Physics 2 (CAS PY 106) satisfies premedical requirements; presupposes knowledge of algebra and trigonometry. PY106 covers the principles of classical and modern physics: electricity and magnetism, waves, optics, light, atomic and nuclear physics.
Students must register for three sections: a lecture section, discussion section, and laboratory section.


Past courses:

PY105 Elementary Physics 1, Summer-II 2017 (4 credits)
Elementary Physics 1 (CAS PY 105) sequence satisfies premedical requirements; presupposes knowledge of algebra and trigonometry. Principles of classical and modern physics, mechanics, conservation laws, and heat.
Students must register for three sections: a lecture section, a discussion section, and a laboratory section.

PY105 Elementary Physics 1, Spring 2017 (4 credits)
Elementary Physics 1 (CAS PY 105) sequence satisfies premedical requirements; presupposes knowledge of algebra and trigonometry. Principles of classical and modern physics, mechanics, conservation laws, and heat.
Students must register for three sections: a lecture section, a discussion section, and a laboratory section.

PY106 Elementary Physics 2, Fall 2016 (4 credits)
Elementary Physics 2 (CAS PY 106) satisfies premedical requirements; presupposes knowledge of algebra and trigonometry. PY106 covers the principles of classical and modern physics: electricity and magnetism, waves, optics, light, atomic and nuclear physics.
Students must register for three sections: a lecture section, discussion section, and laboratory section.




Curriculum Vitae

Key skills

  Modeling complex molecular systems, from liquid water to crystal lattices to large cross-linked network structures

  Molecular Dynamics expert, able to develop home-made code as well as adding code to existing software such as Gromacs and LAMMPS

  Able to explain and teach difficult concepts in a manner anyone can understand

  Expert in computer systems, from developing parallel computing software to fixing hardware to building RAIDs


Honors & Awards:

2017: Schlumberger / Boston University Research Fellowship Grant (extended)

2016: Schlumberger / Boston University Research Fellowship Grant

2015: Teaching-As-Research (TAR) Fellowship (Boston University)

2010: Chair's book award for Excellence in Teaching (Boston University)

2006: Teaching Fellowship (Boston University)

2004: CERN summer student (CERN, Geneva, Switzerland)


Education:


Research Experience:


Conference Presentations:


Teaching Experience:


Miscellaneous Interests:




Publications

  1. JCP Renjie Chen, Erik Lascaris, and Jeremy C. Palmer,
    Liquid-liquid Phase Transition in an Ionic Model of Silica (PDF),
    J. of Chem. Phys. 146, 234503 (2017)
    doi:10.1063/1.4984335

  2. P. Gallo, K. Amann-Winkel, C. A. Angell, M. A. Anisimov, F. Caupin, C. Chakravarty, Erik Lascaris, T. Loerting, A. Z. Panagiotopoulos, J. Russo, J. A. Sellberg, H. E. Stanley, H. Tanaka, C. Vega, L. Xu, and L. G. M. Pettersson,
    Water: A Tale of Two Liquids (PDF),
    Chem. Rev. 116, 7463-7500 (2016)
    doi:10.1021/acs.chemrev.5b00750

  3. PRL Erik Lascaris
    Tunable Liquid-Liquid Critical Point in an Ionic Model of Silica (PDF),
    Phys. Rev. Lett. 116, 125701 (2016)
    doi:10.1103/PhysRevLett.116.125701

  4. JCP Erik Lascaris, M. Hemmati, S. V. Buldyrev, H. E. Stanley, and C. A. Angell,
    Diffusivity and Short-Time Dynamics in Two Models of Silica (PDF),
    J. of Chem. Phys. 142, 104506 (2015)
    doi:10.1063/1.4913747

  5. JCP Erik Lascaris, M. Hemmati, S. V. Buldyrev, H. E. Stanley, and C. A. Angell,
    Search for a Liquid-Liquid Critical Point in Models of Silica (PDF),
    J. of Chem. Phys. 140, 224502 (2014)
    doi:10.1063/1.4879057

  6. PRL J. Luo, L. Xu, Erik Lascaris, H. E. Stanley, and S. V. Buldyrev,
    Behavior of the Widom Line in Critical Phenomena (PDF),
    Phys. Rev. Lett. 112, 135701 (2014)
    doi:10.1103/PhysRevLett.112.135701

  7. JCP T. A. Kesselring, Erik Lascaris, G. Franzese, S. V. Buldyrev, H. J. Herrmann, and H. E. Stanley,
    Finite-size scaling investigation of the liquid-liquid critical point in ST2 water and its stability with respect to crystallization (PDF),
    J. of Chem. Phys. 138, 244506 (2013)
    doi:10.1063/1.4808355

  8. Erik Lascaris, T. A. Kesselring, G. Franzese, S. V. Buldyrev, H. J. Herrmann, and H. E. Stanley,
    Response Functions near the Liquid-Liquid Critical Point of ST2 Water (PDF),
    AIP Conf. Proc. 1518, 520 (2013)
    doi:10.1063/1.4794628

  9. PRE Erik Lascaris, G. Malescio, S. V. Buldyrev, and H. E. Stanley,
    Cluster formation, waterlike anomalies, and re-entrant melting for a family of bounded repulsive interaction potentials (PDF),
    Phys. Rev. E 81, 031201 (2010)
    doi:10.1103/PhysRevE.81.031201

  10. J. Colle, Erik Lascaris, and I. C. Tánczos,
    The HiSPARC project; Science, technology and education (PDF),
    AIP Conf. Proc. 944, 44 (2007)
    doi:10.1063/1.2818548



Contact

Email:
erikl at bu.edu

Office Address:
Erik Lascaris
590 Commonwealth Avenue, room 215
Boston, MA 02215 United States of America

ResearchGate:
www.researchgate.net/profile/Erik_Lascaris

RateMyProfessors.com:
www.ratemyprofessors.com/ShowRatings.jsp?tid=2188879

 LinkedIn:
www.linkedin.com/in/erik-lascaris-84859023/

ORCID:
0000-0002-4385-1740