with their epitaxial precision, make vdW-based devices a promising alternative for constructing key elements of novel solid-state quantum 61st Electronic Materials Conference computing platforms. In particular, these new material systems have the potential to improve coherent characteristics in quantum systems while reducing the footprint of individual qubit –– both are keys to realizing SESSION A: EMC Awards Ceremony and Plenary Session extensible quantum computing schemes. We demonstrate quantum Session Chairs: Kris Bertness and Suzanne Mohney coherent control of a superconducting circuit incorporating graphene- Wednesday Morning, June 26, 2019 based vdW heterostructures. We show that this device can be operated as a Michigan League, 2nd Floor, Lydia Mendelssohn Theatre voltage-tunable transmon qubit, whose spectrum refl ects the electronic properties of massless Dirac fermions traveling ballistically. In addition to * Plenary Paper the potential for advancing extensible quantum computing technology, our results represent a new approach to studying vdW materials using microwave photons in coherent quantum circuits. 8:20 AM EMC Awards Ceremony 10:40 AM B02 8:30 AM *A01 (Student) Nonperturbative Multiphoton Absorption in Gallium Programmable Quantum Materials Dmitri N. Basov; Columbia Nitrides Haiyi Liu1, Qile Wu1, Ping Wang1, Zetian Mi1, Steven T. Cundiff 1, University, New York, New York, United States. 2 and Mackillo Kira1; 1Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan, United States; Experimentally realizing quantum phases of matter and controlling their 2Department of Physics, University of Michigan–Ann Arbor, Ann Arbor, properties is a central goal of the physical sciences. Novel quantum phases Michigan, United States. with controllable properties are essential for new electronic, photonic, and energy management technologies needed to address the growing Gallium nitride (GaN) nanostructures can be designed to have a bandgap societal demands for rapid and energy effi cient information processing from near infrared to ultraviolet (UV) regime by using suitable and transduction[1]. Quantum materials off er particularly appealing heterostructures. By utilizing the large bandgap diff erences between opportunities for the implementation of on-demand quantum phases. This heterostructure layers, one can realize extreme confi nement, even single- class of materials host interacting many-body electronic systems featuring monolayer structures that exhibit very strong excitonic binding energy up an intricate interplay of topology, reduced dimensionality, and strong to hundreds of meV [Appl. Phys. Lett. 109, 241102 (2016)] due to correlations that leads to the emergence of “quantum matter’’ exhibiting enhanced Coulomb interactions. We will present new ways of exciting macroscopically observable quantum eff ects over a vast range of length such GaN nanostructures with strong light fi elds to drive multiphoton and energy scales. In this talk I will overview recent eff orts to discover, transitions and eventually make the onset of high-harmonic generation characterize and deploy new forms of quantum matter controllable by [Nat. Phys. 7, 138 (2011)] as a foundation for optically driven UV sources light, gating, and nano-mechanical manipulation, eff ectively programming and lightwave electronics [Nat. Phot. 11, 227 (2017), Nature 557, 76 their properties. I will focus on enticing opportunities to investigate novel (2018)]. Even though multiphoton transitions in solids can be qualitatively quantum phenomena using nascent nano-optical methods developed in understood with perturbative approaches we clearly need to address the my group[2],[3]. [1] D.N. Basov, R.D. Averitt and D. Hsieh, “Towards massive Coulombic and nonperturbative modifi cations which strong-fi eld properties on demand in quantum materials” Nature Materials 16, 1077 excitations will create in GaN. We will present new quantum-theory (2017). [2] S. S. Sunku, G. X. Ni, B. Y. Jiang, H. Yoo, A. Sternbach, A. S. insights for multiphoton absorption with respect to excitonic as well as McLeod, T. Stauber, L. Xiong, T. Taniguchi, K. Watanabe, P. Kim, M. M. plasma emission properties. The results are compared with our fi rst Fogler, D. N. Basov “Photonic crystals for nano-light in moiré graphene experiment on GaN monolayers. Our realistic quantum theory is based on superlattices” Science 362, 1153–1156 (2018). [3] G. X. Ni, A. S. dynamic cluster expansion which allows for a completely systematic McLeod, Z. Sun, L. Wang, L. Xiong, K. W. Post, S. S. Sunku, B.-Y. Jiang, inclusion of the nonperturbative light-matter and Coulombic interactions. J. Hone, C. R. Dean, M. M. Fogler & D. N. Basov “Fundamental limits to In a solid, a strong non-resonant light excitation creates a large set of graphene plasmonics” Nature 557, 530 (2018). optical coherences, polarization, as well as electron and hole densities. As we have shown earlier [Nat. Phot. 8, 119 (2014)], the polarization and 9:20 AM REFRESHMENT BREAK densities mix together to generate a signifi cant and transient carrier production for high-harmonic conditions. Especially, considering only either polarization or densities would essentially eliminate the relevant excitations. At the same time, the simultaneous presence of polarization SESSION B: Control of Quantum Systems and densities yields excitation induced dephasing for coherences, initiated Session Chairs: Steven Cundiff and Kris Bertness by scattering of polarization with densities. These scattering events need Wednesday Morning, June 26, 2019 some time to build up, typically a few to hundreds of femtoseconds, such Michigan League, 2nd Floor, Lydia Mendelssohn Theatre that dephasing will acquire quantum memory, i.e. dephasing of polarization at a given time depends on polarization at earlier times. This ultrafast onset of dephasing matches the timescales relevant for high- ** Invited Paper harmonic generation/multiphoton transitions, therefore must be included for a realistic quantum theory. We will demonstrate that the quantum- 10:00 AM **B01 memory eff ects indeed play a crucial role in determining the yield of Coherent Control of Graphene-Based Van der Waals Heterostructures multiphoton transitions. In particular, we fi nd that the multiphoton carrier Joel I-Jan Wang1, Daniel Rodan-Legrain2, Charlotte Bøttcher3, Landry production becomes incorrectly dominated by non-resonant single-photon Bretheau4, Daniel L. Campbell1, Bharath Kannan7, David Kim5, Morten absorption when quantum-memory eff ects are ignored. This yields not Kjaergaard1, Philip Krantz1, Gabriel O. Samach5, Fei Yan1, Jonilyn L. only quantitative inaccuracy but also a qualitatively incorrect prediction Yoder5, Megan Yamoah2, 7, Kenji Watanabe6, Takashi Taniguchi6, Terry P. that multiphoton resonances cannot be detected, contradicting with Orlando1, 7, Simon Gustavsson1, Pablo Jarillo-Herrero2 and William D. experiments. Only a theory that fully includes quantum-memory eff ects Oliver1, 2, 5; 1Research Laboratory of Electronics, Massachusetts Institute of can predict qualitatively and quantitatively correct multiphoton absorption Technology, Cambridge, Massachusetts, United States; 2Department of resonances dominated by high-order processes. We will show how Physics, Massachusetts Institute of Technology, Cambridge, including quantum memory at the correct level produces distinct Massachusetts, United States; 3Department of Physics, Harvard University, multiphoton resonances and scaling at the perturbative regime, and how Cambridge, Massachusetts, United States; 4Laboratoire des Solides they are modifi ed in the nonperturbative regime. Our quantitatively correct Irradiés, Ecole Polytechnique, CNRS, CEA, Palaiseau, France; 5Lincoln approach also allows us to quantify a massive Coulomb enhancement of Laboratory, Massachusetts Institute of Technology, Cambridge, multiphoton transitions near and below the bandgap as a function of Massachusetts, United States; 6Advanced Materials Laboratory, National driving fi eld strength. We also show how perturbative results are modifi ed Institute for Materials Science, Tsukuba, Japan; 7Department of Electrical as excitations are made stronger, approaching the regime of lightwave Engineering and Computer Science, Massachusetts Institute of electronics and high-harmonic generation. In summary, our theory Technology, Cambridge, Massachusetts, United States. advancements will provide a new framework for designing GaN-based lightwave electronics realistically. Van der Waals (vdW) materials – a family of layered crystals with various functionalities, can be assembled in specifi c arrangements to create new electronic devices called vdW heterostructures. The extraordinary and versatile electronic properties of these heterostructures, in combination 21 11:00 AM B03 signatures of exciton-phonon coupling in perovskite nanocrystals. These Semiconducting Carbon Nanotube Polaritonics Jialiang Wang1, Abitha attractive properties suggest that the triplet states in these NCs have Dhavamani1, Louis Haeberlé2, Stephane Kena-Cohen2 and Michael S. potential for a perovskite analogue of valleytronics [Langer et al., Nature Arnold1; 1Materials Science and Engineering, University of Wisconsin- 557, (2018)], in which quantum information protocols involving circularly Madison, Madison, Wisconsin, United States; 2Engineering Physics, polarized valley excitons in 2D materials instead use linearly polarized Polytechnique Montréal, Montréal, Quebec, Canada. triplet excitons