
Mathieu Ouellet
Ph.D. Student, Electrical Engineering
200 S. 33rd St
201 Moore Building
Philadelphia, PA 19104
Email: ouellet@seas.upenn.edu
Phone: (215) 898-8312
Fax: (215) 573-2068
Mathieu received a B.S. in Physics, a B.S. in Computer Science and a M.Sc. in Applied Mathematics from the University of Quebec. His research focused on supersymmetric representation of solutions of the Sturm-Liouville problem and on quantification of mitochondrial networks. His current research interests include complex systems, network science and quantum systems.
![]() | Shulevitz, Henry J; Amirshaghaghi, Ahmad; Ouellet, Mathieu; Brustoloni, Caroline; Yang, Shengsong; Ng, Jonah J; Huang, Tzu-Yung; Jishkariani, Davit; Murray, Christopher B; Tsourkas, Andrew; Kagan, Cherie R; Bassett, Lee C Nanodiamond emulsions for enhanced quantum sensing and click-chemistry conjugation Journal Article Forthcoming Forthcoming. @article{Shulevitz2023, title = {Nanodiamond emulsions for enhanced quantum sensing and click-chemistry conjugation}, author = {Henry J. Shulevitz and Ahmad Amirshaghaghi and Mathieu Ouellet and Caroline Brustoloni and Shengsong Yang and Jonah J. Ng and Tzu-Yung Huang and Davit Jishkariani and Christopher B. Murray and Andrew Tsourkas and Cherie R. Kagan and Lee C. Bassett}, url = {https://arxiv.org/abs/2311.16530}, doi = {10.48550/arXiv.2311.16530}, year = {2023}, date = {2023-12-04}, abstract = {Nanodiamonds containing nitrogen-vacancy (NV) centers can serve as colloidal quantum sensors of local fields in biological and chemical environments. However, nanodiamond surfaces are challenging to modify without degrading their colloidal stability or the NV center's optical and spin properties. Here, we report a simple and general method to coat nanodiamonds with a thin emulsion layer that preserves their quantum features, enhances their colloidal stability, and provides functional groups for subsequent crosslinking and click-chemistry conjugation reactions. To demonstrate this technique, we decorate the nanodiamonds with combinations of carboxyl- and azide-terminated amphiphiles that enable conjugation using two different strategies. We study the effect of the emulsion layer on the NV center's spin lifetime, and we quantify the nanodiamonds' chemical sensitivity to paramagnetic ions using T1 relaxometry. This general approach to nanodiamond surface functionalization will enable advances in quantum nanomedicine and biological sensing.}, keywords = {}, pubstate = {forthcoming}, tppubtype = {article} } Nanodiamonds containing nitrogen-vacancy (NV) centers can serve as colloidal quantum sensors of local fields in biological and chemical environments. However, nanodiamond surfaces are challenging to modify without degrading their colloidal stability or the NV center's optical and spin properties. Here, we report a simple and general method to coat nanodiamonds with a thin emulsion layer that preserves their quantum features, enhances their colloidal stability, and provides functional groups for subsequent crosslinking and click-chemistry conjugation reactions. To demonstrate this technique, we decorate the nanodiamonds with combinations of carboxyl- and azide-terminated amphiphiles that enable conjugation using two different strategies. We study the effect of the emulsion layer on the NV center's spin lifetime, and we quantify the nanodiamonds' chemical sensitivity to paramagnetic ions using T1 relaxometry. This general approach to nanodiamond surface functionalization will enable advances in quantum nanomedicine and biological sensing. |
![]() | Poteshman, Abigail N; Ouellet, Mathieu; Bassett, Lee C; Bassett, Dani S Network structure and dynamics of effective models of nonequilibrium quantum transport Journal Article Physical Review Research, 5 , pp. 023125, 2023. @article{Poteshman2023, title = {Network structure and dynamics of effective models of nonequilibrium quantum transport}, author = {Abigail N. Poteshman and Mathieu Ouellet and Lee C. Bassett and Dani S. Bassett}, url = {https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.023125}, doi = {10.1103/PhysRevResearch.5.023125}, year = {2023}, date = {2023-05-26}, journal = {Physical Review Research}, volume = {5}, pages = {023125}, abstract = {Across all scales of the physical world, dynamical systems can be usefully represented as abstract networks that encode the systems' units and interunit interactions. Understanding how physical rules shape the topological structure of those networks can clarify a system's function and enhance our ability to design, guide, or control its behavior. In the emerging area of quantum network science, a key challenge lies in distinguishing between the topological properties that reflect a system's underlying physics and those that reflect the assumptions of the employed conceptual model. To elucidate and address this challenge, we study networks that represent nonequilibrium quantum-electronic transport through quantum antidot devices—an example of an open, mesoscopic quantum system. The network representations correspond to two different models of internal antidot states: a single-particle, noninteracting model and an effective model for collective excitations including Coulomb interactions. In these networks, nodes represent accessible energy states and edges represent allowed transitions. We find that both models reflect spin conservation rules in the network topology through bipartiteness and the presence of only even-length cycles. The models diverge, however, in the minimum length of cycle basis elements, in a manner that depends on whether electrons are considered to be distinguishable. Furthermore, the two models reflect spin-conserving relaxation effects differently, as evident in both the degree distribution and the cycle-basis length distribution. Collectively, these observations serve to elucidate the relationship between network structure and physical constraints in quantum-mechanical models. More generally, our approach underscores the utility of network science in understanding the dynamics of quantum systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Across all scales of the physical world, dynamical systems can be usefully represented as abstract networks that encode the systems' units and interunit interactions. Understanding how physical rules shape the topological structure of those networks can clarify a system's function and enhance our ability to design, guide, or control its behavior. In the emerging area of quantum network science, a key challenge lies in distinguishing between the topological properties that reflect a system's underlying physics and those that reflect the assumptions of the employed conceptual model. To elucidate and address this challenge, we study networks that represent nonequilibrium quantum-electronic transport through quantum antidot devices—an example of an open, mesoscopic quantum system. The network representations correspond to two different models of internal antidot states: a single-particle, noninteracting model and an effective model for collective excitations including Coulomb interactions. In these networks, nodes represent accessible energy states and edges represent allowed transitions. We find that both models reflect spin conservation rules in the network topology through bipartiteness and the presence of only even-length cycles. The models diverge, however, in the minimum length of cycle basis elements, in a manner that depends on whether electrons are considered to be distinguishable. Furthermore, the two models reflect spin-conserving relaxation effects differently, as evident in both the degree distribution and the cycle-basis length distribution. Collectively, these observations serve to elucidate the relationship between network structure and physical constraints in quantum-mechanical models. More generally, our approach underscores the utility of network science in understanding the dynamics of quantum systems. |