BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Brian Skinner (Ohio State UNiversity) DTSTART:20201014T171500Z DTEND:20201014T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/1 DESCRIPTION:Title: Measurement-induced Phase Transitions in the Dynamics of Quantum Ent anglement\nby Brian Skinner (Ohio State UNiversity) as part of VSF Lon g Range Colloquium\n\n\nAbstract\nWhen a quantum system evolves under unit ary dynamics\, as produced by either a Hamiltonian or by a sequence of qua ntum gates\, its various component parts tend to become more entangled wit h each other. Making measurements\, on the other hand\, tends to reduce th is entanglement by collapsing some of the system's degrees of freedom. In this talk we explore what happens to the entanglement when a quantum many- body system undergoes both unitary evolution and sporadic measurements. We show that the competition between these two effects leads to a new kind o f dynamical phase transition\, such that when the measurement rate is lowe r than a critical value the dynamics is "entangling"\, while a higher-than -critical measurement rate leads to a "disentangling" phase. We study this transition both in one-dimensional spin chains and in "all-to-all" couple d systems\, for which unitary operators can directly couple any two degree s of freedom. In both cases the qualitative features of the transition can be understood by mapping to a problem of classical percolation\, and in t he all-to-all case some features of the transition can be understood exact ly.\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Natalia Ares (University of Oxford) DTSTART:20201028T171500Z DTEND:20201028T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/2 DESCRIPTION:Title: Measuring and tuning quantum devices faster than human experts\n by Natalia Ares (University of Oxford) as part of VSF Long Range Colloquiu m\n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Jennifer Cano (Stony Brook University) DTSTART:20201111T181500Z DTEND:20201111T194500Z DTSTAMP:20260404T111136Z UID:VSFLRC/3 DESCRIPTION:Title: Higher magic angles in twisted bilayer graphene and topological twis tronics\nby Jennifer Cano (Stony Brook University) as part of VSF Long Range Colloquium\n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Deji Akinwande (University of Texas at Austin) DTSTART:20201209T181500Z DTEND:20201209T194500Z DTSTAMP:20260404T111136Z UID:VSFLRC/4 DESCRIPTION:Title: 2D materials: From atoms to applications\nby Deji Akinwande (Uni versity of Texas at Austin) as part of VSF Long Range Colloquium\n\n\nAbst ract\nThis talk will present our latest research adventures on 2D nanomate rials towards greater scientific understanding and advanced engineering ap plications. In particular\, the talk will highlight our work on flexible e lectronics\, zero-power devices\, monolayer memory (atomristors)\, non-vol atile RF switches\, and wearable tattoo sensors. Non-volatile memory devic es based on 2D materials represent an application of defects and are a rap idly advancing field with rich physics that can be attributed to sulfur va cancies or metal diffusion. Atomistic modeling and atomic-resolution imagi ng are contemporary tools used to elucidate the memory phenomena in these systems. Likewise\, from a practical point of view\, electronic tattoos ba sed on graphene have ushered a new material platform that has highly desir able practical attributes including optical transparency\, mechanical impe rceptibility\, and is the thinnest conductive electrode sensor that can be integrated on skin for physiological measurements.\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Leonid Levitov (MIT) DTSTART:20210120T181500Z DTEND:20210120T194500Z DTSTAMP:20260404T111136Z UID:VSFLRC/5 DESCRIPTION:Title: Electrons Bloch-waltzing in Moire superlattices\nby Leonid Levit ov (MIT) as part of VSF Long Range Colloquium\n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Andrea Young (UCSB) DTSTART:20210203T181500Z DTEND:20210203T194500Z DTSTAMP:20260404T111136Z UID:VSFLRC/6 DESCRIPTION:Title: Orbital magnetism in graphene heterostructures\nby Andrea Young (UCSB) as part of VSF Long Range Colloquium\n\n\nAbstract\nThe earliest re ports of ferromagnetism date to Thales of Miletus who lived and wrote arou nd 600 BC. Thales noted the ability of natural magnetite to attract iron\, and is said to have taken this as proof that matter itself was alive. Our theories of magnetism have evolved considerably since then: we now know t hat ferromagnetism arises from the interplay of the Coulomb repulsion betw een electrons and their fermionic statistics. However\, in one sense our s cience has advanced only little: the vast majority of magnets\, like magne tite\, consist of ordered arrangements of the electron spins stabilized by the spin orbit interaction. In my talk\, I will describe a new class of m agnets based on the spontaneous alignment of electron orbitals. Such orbit al ferromagnetism may be a generic phenomena\, but has\, to date\, found i ts fullest expression in graphene heterostructures in which the two dimens ional orbits of electrons in distinct momentum space valleys provide the u nderlying degree of freedom. Because orbital degrees of freedom arise dire ctly from the band wavefunctions\, they are uniquely susceptible to experi mental control via materials design. Orbital magnets also enable new forms of magnetic control using in situ knobs. For instance\, orbital magnets i n moire superlattice systems\, where the band structure features nontrivia l topology\, allow for field-effect switching of magnetic moments and the resulting quantized anomalous Hall effects. I will conclude with an outloo k for realizing more exotic topological phases of matter based on orbital magnetism.\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Xie Chen (Caltech) DTSTART:20210217T181500Z DTEND:20210217T194500Z DTSTAMP:20260404T111136Z UID:VSFLRC/7 DESCRIPTION:Title: Fracton and Chern-Simons Theory\nby Xie Chen (Caltech) as part o f VSF Long Range Colloquium\n\n\nAbstract\nFracton order describes the pec uliar phenomena that point excitations in certain strongly interacting sys tems either cannot move at all or are only allowed to move in a lower dime nsional sub-manifold. It has recently been discovered in various lattice m odels\, tensor gauge theories\, etc. In this talk\, we discuss how another powerful field theory framework -- the 2+1D Chern-Simons (CS) gauge theor y -- can be used to provide new insight and explore new possibilities in 3 +1D fracton order. 2+1D U(1) gauge theories with a CS term provide a simpl e and complete characterization of 2+1D Abelian topological orders. To stu dy 3+1D fracton order\, we extend the theory by taking the number of compo nent gauge fields to be infinity. In the simplest case of infinite-compone nt CS gauge theory\, different components do not couple to each other and the theory describes a decoupled stack of 2+1D fractional Quantum Hall sys tems with quasi-particles moving only in 2D planes -- hence a fractonic sy stem. More interestingly\, we find that when the component gauge fields do couple through the CS term\, more varieties of fractonic orders are possi ble. For example\, they may describe foliated fractonic systems which exte nds the framework found in exactly solvable models. Moreover\, we find exa mples which lie beyond the foliation framework\, characterized by 2D excit ations of infinite order and braiding statistics that are not strictly loc al.\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Monika Aidelsburger (LMU Munich) DTSTART:20210303T181500Z DTEND:20210303T194500Z DTSTAMP:20260404T111136Z UID:VSFLRC/8 DESCRIPTION:Title: Ultracold atoms in optical lattices out-of-equilibrium\nby Monik a Aidelsburger (LMU Munich) as part of VSF Long Range Colloquium\n\n\nAbst ract\nWell-controlled synthetic quantum systems\, such as ultracold atoms in optical lattices\, offer intriguing possibilities to study complex many -body problems relevant to a variety of research areas\, ranging from cond ensed matter to high-energy physics. In particular\, out-of-equilibrium ph enomena constitute natural applications of quantum simulators\, which have already successfully demonstrated simulations in regimes that are beyond reach using state-of-the-art numerical techniques.\nThis enables us to she d new light on fundamental questions about the thermalization of isolated quantum many-body systems. While generic models are expected to thermalize according to the eigenstate thermalization hypothesis (ETH)\, violation o f ETH is believed to occur mainly in two types of systems: integrable mode ls and many-body localized systems. In between these two extreme limits th ere is\, however\, a whole range of models that exhibit more complex dynam ics\, for instance\, due to an emergent fragmentation of the Hilbert space into many dynamically disconnected subspaces. Here\, we realize such a mo del by implementing the 1D Fermi-Hubbard model with a strong linear potent ial [1] and observe strong initial-state dependent thermalization - a smok ing-gun signature of Hilbert-space fragmentation.\nEngineering quantum sys tems out-of-equilibrium\, on the other hand\, further can be used as a too l to engineer novel quantum phases of matter\, which cannot be accessed in static realizations. To this end\, the system’s parameters are varied p eriodically\, a method commonly known as Floquet engineering [2]. This fac ilitated the realization of paradigmatic topological lattice models and re cently inspired ideas for implementing Z2 lattice gauge theories [3]. The rich properties of topological Floquet systems\, however\, transcend those of their static counterparts\, resulting in a generalized bulk-edge corre spondence. As a consequence\, topological edge modes can exist even in sit uations where the bulk bands have zero Chern numbers. The novel properties of such anomalous Floquet systems open the door to exciting new non- equi librium many-body phases without any static analogue [4].\n\n[1] S. Scherg et al.\, arXiv:2010.12965 (2020)\n[2] A. Eckardt\, Phys. Mod. Phys. 89\, 311 (2017)\n[3] C. Schweizer et al.\, Nat. Phys. 15\, 1168-1173 (2019)\n[4 ] K. Wintersperger et al.\, Nature Physics 16\, 1058-1063 (2020)\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/8/ END:VEVENT BEGIN:VEVENT SUMMARY:Andy Mackenzie (Max Planck Institute for Chemical Physics of Solid s) DTSTART:20210331T171500Z DTEND:20210331T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/9 DESCRIPTION:Title: Benefits of good old-fashioned crystalline perfection - new physics in ultra pure delafossite metals\nby Andy Mackenzie (Max Planck Insti tute for Chemical Physics of Solids) as part of VSF Long Range Colloquium\ n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/9/ END:VEVENT BEGIN:VEVENT SUMMARY:Andreas Wallraff (ETH Zürich) DTSTART:20210414T171500Z DTEND:20210414T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/10 DESCRIPTION:Title: Microwave Networks for Solid State Quantum Information Processors\nby Andreas Wallraff (ETH Zürich) as part of VSF Long Range Colloquium \n\n\nAbstract\nQuantum computing is a radically new approach to processin g information. It is one of the approaches which has the potential to addr ess the ever-growing need of society\, industry and research for computing power. At ETH Zurich\, we have designed\, realized and tested a first dat a link which allows superconducting-circuit-based quantum processors locat ed in different systems to directly exchange quantum information [1]. This link\, for a quantum computer\, takes the role of a network transferring data between computing nodes located in a high-performance computing data center. However\, unlike its conventional counterparts\, our data link is operated at ultra-low temperatures\, close to the absolute zero. This allo ws our quantum data link to directly connect to quantum processors operati ng at the same temperature [2]. The system we have constructed is a first of its kind in the world and could play an important role in growing the p ower of quantum computers in the future.\n\n[1] P. Magnard et al.\, Phys. Rev. Lett. 125\, 260502 (2020)\n[2] P. Kurpiers et al.\, Nature 558\, 264- 267 (2018)\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/10/ END:VEVENT BEGIN:VEVENT SUMMARY:Michael Sentef (Max Planck Institute for the Structure and Dynamic s of Matter) DTSTART:20210428T171500Z DTEND:20210428T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/11 DESCRIPTION:Title: Cavity quantum materials\nby Michael Sentef (Max Planck Institu te for the Structure and Dynamics of Matter) as part of VSF Long Range Col loquium\n\n\nAbstract\nRecent years have seen tremendous progress in utili zing ultrafast light-matter interaction to control the macroscopic propert ies of quantum materials [1]. Many of the most intriguing effects are base d on nonthermal pathways\, with the material (quantum many-body system) be ing driven away from its thermal equilibrium by strong laser pulses. While this has deepened our understanding of quantum matter far from equilibriu m and enabled us to build bridges to other fields (quantum simulators\, Fl oquet states of matter\, (pre)thermalization\, …)\, there are a number o f challenges: (i) the need for strong lasers\, (ii) heating\, (iii) short lifetime of light-induced states.\n\nThis has motivated an emergent commun ity of researchers to search for new directions that draw inspiration from the discoveries in ultrafast materials science and combine them with expe rtise gleaned from quantum optics\, cavity QED\, polaritonic chemistry\, a nd nanoplasmonics\, creating the new field of "cavity quantum materials“ .\n\nIn this Colloquium\, I will provide a personal perspective on this ne w field and highlight a few of our recent works. Specifically\, I will dis cuss the quantum-to-classical crossover of Floquet engineering in correlat ed systems and show how a many-photon classical coherent state can be repl aced by a few-photon number state\, provided that one can reach the regime of sufficiently strong light-matter coupling in a cavity [2]. I will then show how the quantum geometry of wavefunctions impacts their light-matter coupling\, and how we envision this to be a key ingredient for future lig ht-matter-based engineering of flat-band (Moiré) materials [3].\n\n[1] A. de la Torre\, D. M. Kennes\, M. Claassen\, S. Gerber\, J. W. McIver\, M. A. Sentef\, Nonthermal pathways to ultrafast control in quantum materials\ , arXiv:2103.14888\n\n[2] M . A. Sentef\, J. Li\, F. Künzel\, M. Eckstein\, Quantum to classical cros sover of Floquet engineering in correlated quantum systems\, Phys. Rev. Re search 2\, 033033 (2020) [3] G. E. Topp\, C. J. Eckhardt\, D. M. Kennes\, M. A. Sentef\, P. Törmä\, Light-matter coupling and quantum geometry in moiré materials\, arXiv:2103.0 4967\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/11/ END:VEVENT BEGIN:VEVENT SUMMARY:Jonathan Simon (University of Chicago) DTSTART:20210512T171500Z DTEND:20210512T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/12 DESCRIPTION:Title: When Photons Self-Organize: Making Matter from Light\nby Jonath an Simon (University of Chicago) as part of VSF Long Range Colloquium\n\nA bstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/12/ END:VEVENT BEGIN:VEVENT SUMMARY:Giuseppe Carleo (EPFL Lausanne) DTSTART:20210526T171500Z DTEND:20210526T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/13 DESCRIPTION:by Giuseppe Carleo (EPFL Lausanne) as part of VSF Long Range C olloquium\n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/13/ END:VEVENT BEGIN:VEVENT SUMMARY:Richard Kueng DTSTART:20210901T171500Z DTEND:20210901T184500Z DTSTAMP:20260404T111136Z UID:VSFLRC/14 DESCRIPTION:Title: Provably efficient machine learning for quantum many-body problems< /a>\nby Richard Kueng as part of VSF Long Range Colloquium\n\nAbstract: TB A\n LOCATION:https://stable.researchseminars.org/talk/VSFLRC/14/ END:VEVENT END:VCALENDAR