BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Martin Frimmer (ETH Zurich) DTSTART:20200629T160000Z DTEND:20200629T170000Z DTSTAMP:20260404T110826Z UID:QuantumHuddle/1 DESCRIPTION:Title: Optomechanics with a levitated nanoparticle\nby Martin Fr immer (ETH Zurich) as part of Quantum Huddle\n\n\nAbstract\nLevitated opto mechanics exploits the forces of light to suspend nanoscopic objects in va cuum. The light field serves both as a handle to mechanically manipulate\, but also to interrogate various mechanical degrees of freedom of a levita ted particle. In our talk\, we introduce the audience to the field of levi tated optomechanics\, and discuss recent experimental progress towards ful l optomechanical control of the rotational and translational degrees of fr eedom of a levitated nanoparticle. In particular\, we focus on feedback co oling a levitated particle’s motion to the few-phonon regime\, where fir st signatures of its motional ground state emerge.\n\nMartin studied physi cs at the Technical University of Munich. He performed his PhD work at the AMOLF Institute in Amsterdam in the field of nano-optics. Currently\, Mar tin is a lecturer and research scientist at the Photonics Laboratory of ET H Zurich\, where he focuses on optomechanics with optically levitated nano particles.\n LOCATION:https://stable.researchseminars.org/talk/QuantumHuddle/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Javier Aizpurua (UPV/EHU) DTSTART:20200706T160000Z DTEND:20200706T170000Z DTSTAMP:20260404T110826Z UID:QuantumHuddle/2 DESCRIPTION:Title: Photoinduced electron dynamics in metallic nanogaps from firs t principles calculations\nby Javier Aizpurua (UPV/EHU) as part of Qua ntum Huddle\n\n\nAbstract\nA nanoscale gap between two metallic nanopartic les is an ideal platform to exploit the interplay between electron current s and photonic excitations. The capability of a metallic gap to enhance th e amplitude of the induced plasmonic field produces a variety of non-linea r effects [1\,2] which can be exploited in different applications in optoe lectronics\, such as optical rectification\, light emission driven by DC c urrents\, or high-harmonic generation\, among others. Furthermore\, in ult ranarrow gaps\, tunneling of electrons at optical frequencies has been fou nd to screen the plasmonic bonding gap resonance\, and activate a new dist ribution of optical modes characterized by optical charge transfer [3].\n\ nHere we address the complex dynamics of photoelectrons driven by single-c ycle optical pulses in nanoscale gaps. By solving Schrödinger equation wi thin the framework of Time-Dependent Density Functional Theory (TDDFT)\, t he currents of the electrons photoemitted across the gap can be monitored\ , identifying ultrafast electron bursts where electron quiver occurs when the amplitude of the induced field at the plasmonic gap is reversed within the optical cycle. The properties of the amplitude and carrier-envelope p hase (CEP) of the incident pulse\, together with the gap length determine the complex electron dynamics [4\,5\,6]. \n\nExperimental measurements of the current autocorrelations for pairs of such pulses with controlled rela tive delay between them\, confirms the ultrafast dynamics of the photoelec trons in the gap and its complexity.\n\nReferences\n[1] D.C. Marinica et a l.\, "Quantum plasmonics: nonlinear effects in the field enhancement of a plasmonic dimer". Nano Lett. 12\, 1333 (2012).\n[2] A. Babaze et al.\, "Se cond-Harmonic Generation from a Quantum Emitter Coupled to a Metallic Nano antenna". ACS Photonics 7\, 701-713 (2020) .\n[3] K.J. Savage et al.\, "Re vealing the quantum regime in tunneling plasmonics". Nature 491\, 574 (201 2).\n[4] G. Aguirregabiria et al.\, "Dynamics of electron-emission current s in plasmonic gaps induced by strong fields". Faraday Discussions 214\, 1 47-157 (2019).\n[5] M. Ludwig et al.\, "Sub-femtosecond electron transport in a nanoscale gap". Nature Physics 16\, 341–345 (2020).\n[6] M. Ludwig et al. "Active control of ultrafast electron dynamics in plasmonic gaps u sing an applied bias"\, Phys. Rev. B 101\, 241412(R) (2020).\n LOCATION:https://stable.researchseminars.org/talk/QuantumHuddle/2/ END:VEVENT BEGIN:VEVENT SUMMARY:David Mazziotti (The University of Chicago) DTSTART:20200713T160000Z DTEND:20200713T170000Z DTSTAMP:20260404T110826Z UID:QuantumHuddle/3 DESCRIPTION:Title: Preparation of an exciton condensate on a 53 qubit quantum co mputer\nby David Mazziotti (The University of Chicago) as part of Quan tum Huddle\n\n\nAbstract\nQuantum computation promises an exponential spee dup of certain classes of classical calculations through the preparation a nd manipulation of entangled quantum states. So far most molecular simulat ions on quantum computers\, however\, have been limited to small numbers o f particles. In this talk I will discuss our research group's recent prepa ration of a highly entangled state on a 53-qubit IBM quantum computer\, re presenting 53 particles\, which reveals the formation of an exciton conden sate of photon particles and holes. More generally\, I will discuss recent research efforts in our group directed towards exploiting the potential a dvantage of quantum computing for chemistry.\n LOCATION:https://stable.researchseminars.org/talk/QuantumHuddle/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Danna Freedman (Northwestern University) DTSTART:20200727T160000Z DTEND:20200727T170000Z DTSTAMP:20260404T110826Z UID:QuantumHuddle/4 DESCRIPTION:Title: Chemistry for the second quantum revolution\nby Danna Fre edman (Northwestern University) as part of Quantum Huddle\n\n\nAbstract\nC hemistry offers an atomically precise way to synthesize qubits. By harness ing chemical precision we can place atoms exactly where we want them. Rese arch on constructing chemical qubits and understanding their coherence pro perties will be presented. Recent results on creating optically addressabl e molecular qubits or molecular color centers will be highlighted.\n LOCATION:https://stable.researchseminars.org/talk/QuantumHuddle/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Juan Carlos Idrobo (Center for Nanophase Materials Sciences\, Oak Ridge National Laboratory) DTSTART:20200720T160000Z DTEND:20200720T170000Z DTSTAMP:20260404T110826Z UID:QuantumHuddle/5 DESCRIPTION:Title: 2020 A New Resolution Odyssey: An Electron Microscope for Qua ntum Materials Research\nby Juan Carlos Idrobo (Center for Nanophase M aterials Sciences\, Oak Ridge National Laboratory) as part of Quantum Hudd le\n\n\nAbstract\nHere\, I will present several examples demonstrating how the new generation of monochromators\, aberration-correctors and cameras in STEM can rival the capabilities of synchrotrons and allow to probe mate rials behavior at the nanometer and atomic scales in complete new ways. Sp ecifically\, I will show how by utilizing the phase of the electron probe one can reveal the anti-ferromagnetic order of complex-oxide materials [1] \, and explore the ferromagnetic strength at the interfaces of thin-film c omplex-oxide heterostructures [2] at the atomic level. I will also explain how STEM can be used to detect site-specific isotopic labels in amino aci ds at the nanometer scale [3]\, and show our current efforts in obtaining a vibrational spectroscopy atlas of all proteinogenic amino acids via EELS . Lastly\, I will discuss potentially relevant new challenges that electro n microscopy will need to resolve in the future. Would it be possible to m ap orbitals and spins with atomic resolution and with single atom sensitiv ity? Could we detect a superconducting transition? Could we detect minute concentrations of isotopic elements and perform radiocarbon dating at the nanoscale? These questions will be addressed and further elaborated during the presentation [4]. References: [1] J. C. Idrobo\, et al.\, Adv. Struc. Chem. Img. 2 (2016)\, p. 5. [2] J. C. Idrobo\, et al.\, unpublished (2020 ). [3] J. A. Hachtel\, et al.\, Science 363 (2019)\, p. 525. [4] This rese arch was supported by the Center for Nanophase Materials Sciences\, which is a Department of Energy Office of Science User Facility\, and instrument ation within ORNL's Materials Characterization Core provided by UT-Battell e\, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of E nergy.\n LOCATION:https://stable.researchseminars.org/talk/QuantumHuddle/5/ END:VEVENT END:VCALENDAR