This award supports theoretical and computational research, and education on a new state of electronic matter, topological superconductivity, induced by light. The study of the interaction of light and matter, such as in the frequency dependence or spectrum of light emitted by an excited atom and the photo-electric effect where light on the surface of a material can liberate electrons, played a central role in the development of quantum physics. The interaction of light with quantum mechanical states facilitated technological advances like the development of lasers with wide applications from optical communication to medical devices. On another front, it has been realized that interaction and entanglement of a macroscopic number of electrons could lead to the development of novel quantum mechanical phases, such as superconductivity and topological states. In the former case, electrons participate in a collective bulk quantum mechanical state that can carry electric current without loss. The bulk of a topological insulator, an example of the latter case, is insulating but has a metallic state that covers the surface and edges that can also carry electric current without loss, albeit for reasons different from that of bullk superconducting states. This research project brings the concepts of superconductivity and topological states together by exploring the interaction of light with electrons in layered materials to generate and control a topological superconducting state. The PI aims to advance theoretical understanding of how optically controllable topological superconducting states could be designed, created, and controlled. If realized in the laboratory, these states could form the foundation for the development of the next generation of quantum technologies, such as quantum computers and quantum communication devices which function through the manipulation of quantum mechanical states. This award also supports outreach and educational activities. Minority students underrepresented in science, technology, engineering and math (STEM) related fields will gain cutting-edge research experiences through the outreach efforts in this project. The PI will design a colloquium series related to the technological impacts of the project that will explore everyday applications of quantum physics and their relationship to potential technological revolutions through quantum computing and spintronics. Presentations will be at different venues, including nonprofit organizations devoted to educating African-American students in stem and energizing them to pursue careers in STEM related fields, as well as the CUNY Advanced Science Research Center which provides resources for public outreach in the New York City Harlem neighborhood. The PI will also organize these seminar series in the form of a chapter on quantum properties of materials to be implemented in high-school courses on modern physics. This effort is carried out in collaboration with high-schools in greater New York City.
This award supports theoretical and computational research, and education on topological superconductivity. Signatures of superconductivity observed after the application of laser pulses to certain materials has recently drawn much interest. A major achievement is the realization of superconductivity at temperatures much higher than the equilibrium critical temperature. On another front, it leads to further questions of what other quantum states might be stabilized out-of-equilibrium. The possibility of designer topological phases is particularly interesting and of practical use. The PI will investigate topological superconductivity achieved through the modification of the electronic band structure and control of electron-electron interactions in two-dimensional materials like single layer transition metal dichalcogenides. The PI will study the optical generation of Josephson junctions and vortices, controlled by the specific polarization pattern of the optical pump and the vortex structure of applied light beams. The PI aims to investigate how defects may be used to optically generate excitations such as Majorana states and to examine the dynamical displacement of the defect modes that would generate quantum braiding. The optical signatures of the defect modes and their braiding statistics will be also determined. The PI plans to investigate the effect of thermalization, heating, and disorder on stabilizing these states. Analytical and numerical approaches based on the master equation and Keldysh formalism will be used. Even though the main focus of the project is on topological superconductivity in two-dimensional metal dichalcogenides, the efforts could extend to a wide range of light-induced interacting topological states, such as topological Mott insulators and fractional anomalous Hall phases, in different materials like single layer Bismuth or twisted bilayer graphene depending on theoretical advances that are made as the research is performed.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
