Now showing items 1-20 of 42

    • Acoustic buffeting by infrasound in a low vibration facility 

      MacLeod, B. P.; Hoffman, Jennifer Eve; Burke, S. A.; Bonn, D. A. (AIP Publishing, 2016)
      Measurement instruments and fabrication tools with spatial resolution on the atomic scale require facilities that mitigate the impact of vibration sources in the environment. One approach to protection from vibration in a ...
    • Bounds on nanoscale nematicity in single-layerFeSe/SrTiO3 

      Huang, Dennis; Webb, Tatiana A.; Fang, Shiang; Song, Can-Li; Chang, Cui-Zu; Moodera, Jagadeesh S.; Kaxiras, Efthimios; Hoffman, Jennifer Eve (American Physical Society (APS), 2016)
      We use scanning tunneling microscopy (STM) and quasiparticle interference (QPI) imaging to investigate the low-energy orbital texture of single-layer FeSe/SrTiO3. We develop a T -matrix model of multiorbital QPI to disentangle ...
    • Charge Order Driven by Fermi-Arc Instability in Bi2Sr2-xLaxCuO6+  

      Comin, R.; Frano, A.; Yee, Michael Manchun; Yoshida, Y.; Eisaki, H.; Schierle, E.; Weschke, E.; Sutarto, R.; He, F.; Soumyanarayanan, Anjan; He, Yang; Le Tacon, M.; Elfimov, I. S.; Hoffman, Jennifer Eve; Sawatzky, G. A.; Keimer, B.; Damascelli, A. (American Association for the Advancement of Science (AAAS), 2013)
      The understanding of the origin of superconductivity in cuprates has been hindered by the apparent diversity of intertwining electronic orders in these materials. We combined resonant x-ray scattering (REXS), scanning-tunneling ...
    • Condensed-matter physics: Catching relativistic electrons 

      Zhu, Zhihuai; Hoffman, Jennifer Eve (Nature Publishing Group, 2014)
      Low-energy electrons have been found to mimic relativistic high-energy particles in cadmium arsenide. This defines the first stable '3D Dirac semimetal', which holds promise for fundamental-physics exploration and practical ...
    • Controlled Manipulation of Individual Vortices in a Superconductor 

      Straver, Eric W. J.; Hoffman, Jennifer; Auslaender, Ophir M.; Rugar, Daniel; Moler, Kathryn A. (American Institute of Physics, 2008)
      We report controlled local manipulation of single vortices by low temperature magnetic force microscopy in a thin film of superconducting Nb. We are able to position the vortices in arbitrary configurations and to measure ...
    • Dopant clustering, electronic inhomogeneity, and vortex pinning in iron-based superconductors 

      Song, Can-Li; Yin, Yi; Zech, Martin; Williams, Tess; Yee, Michael Manchun; Chen, Gen-Fu; Luo, Jian-Lin; Wang, Nan-Lin; Hudson, E. W.; Hoffman, Jennifer Eve (American Physical Society (APS), 2013)
      We use scanning tunneling microscopy to map the surface structure, nanoscale electronic inhomogeneity, and vitreous vortex phase in the hole-doped superconductor Sr0.75K0.25Fe2As2 with Tc=32 K. We find that the low-T cleaved ...
    • Dumbbell Defects in FeSe Films: A Scanning Tunneling Microscopy and First-Principles Investigation 

      Huang, Dennis; Webb, Tatiana A.; Song, Can-Li; Chang, Cui-Zu; Moodera, Jagadeesh S.; Kaxiras, Efthimios; Hoffman, Jennifer Eve (American Chemical Society (ACS), 2016)
      The properties of iron-based superconductors (Fe-SCs) can be varied dramatically with the introduction of dopants and atomic defects. As a pressing example, FeSe, parent phase of the highest-Tc Fe-SC, exhibits prevalent ...
    • Etching of Cr tips for scanning tunneling microscopy of cleavable oxides 

      Huang, Dennis; Liu, Stephen; Zeljkovic, Ilija; Mitchell, J. F.; Hoffman, Jennifer Eve (AIP Publishing, 2017)
      We report a detailed three-step roadmap for the fabrication and characterization of bulk Cr tips for spin-polarized scanning tunneling microscopy. Our strategy uniquely circumvents the need for ultra-high vacuum preparation ...
    • Fermi Surface and Pseudogap Evolution in a Cuprate Superconductor 

      He, Yang; Yin, Yi; Zech, M.; Soumyanarayanan, Anjan; Yee, Michael Manchun; Williams, T; Boyer, M. C.; Chatterjee, K.; Wise, W. D.; Zeljkovic, I; Kondo, T.; Takeuchi, T.; Ikuta, H.; Mistark, P.; Markiewicz, R. S.; Bansil, A.; Sachdev, Subir; Hudson, E. W.; Hoffman, Jennifer Eve (American Association for the Advancement of Science (AAAS), 2014)
      The unclear relationship between cuprate superconductivity and the pseudogap state remains an impediment to understanding the high transition temperature (Tc) superconducting mechanism. Here, we used magnetic field–dependent ...
    • Imaging the Electron-Boson Coupling in Superconducting FeSe Films Using a Scanning Tunneling Microscope 

      Song, Can-Li; Wang, Yi-Lin; Jiang, Ye-Ping; Li, Zhi; Wang, Lili; He, Ke; Chen, Xi; Hoffman, Jennifer Eve; Ma, Xu-Cun; Xue, Qi-Kun (American Physical Society (APS), 2014)
      Scanning tunneling spectroscopy has been used to reveal signatures of a bosonic mode in the local quasiparticle density of states of superconducting FeSe films. The mode appears below Tc as a “dip-hump” feature at energy ...
    • Interplay of chemical disorder and electronic inhomogeneity in unconventional superconductors 

      Zeljkovic, Ilija; Hoffman, Jennifer Eve (Royal Society of Chemistry (RSC), 2013)
      Many of today's forefront materials, such as high-Tc superconductors, doped semiconductors, and colossal magnetoresistance materials, are structurally, chemically and/or electronically inhomogeneous at the nanoscale. ...
    • La2−xSrxCuO4 superconductor nanowire devices 

      Litombe, Nicholas E.; Bollinger, A.T.; Hoffman, Jennifer Eve; Božović, I. (Elsevier BV, 2014)
      La2−xSrxCuO4 nanowire devices have been fabricated and characterized using electrical transport measurements. Nanowires with widths down to 80 nm are patterned using high-resolution electron beam lithography. However, the ...
    • Mechanics of Individual, Isolated Vortices in a Cuprate Superconductor 

      Auslaender, Ophir M.; Luan, Lan; Straver, Eric W. J.; Hoffman, Jennifer; Koshnick, Nicholas C.; Zeldov, Eli; Bonn, Douglas A.; Liang, Ruixing; Hardy, Walter N.; Moler, Kathryn A. (Nature Publishing Group, 2009)
      Superconductors often contain quantized microscopic whirlpools of electrons, called vortices, that can be modelled as one-dimensional elastic objects1. Vortices are a diverse area of study for condensed matter because of ...
    • Microcantilever Q Control Via Capacitive Coupling 

      Huefner, Magdalena; Pivonka, Adam; Kim, Jeehoon; Ye, Cun; Blood-Forsythe, Martin Ashby; Zech, Martin; Hoffman, Jenny Eve (American Institute of Physics, 2012)
      We introduce a versatile method to control the quality factor Q of a conducting cantilever in an atomic force microscope (AFM) via capacitive coupling to the local environment. Using this method, Q may be reversibly tuned ...
    • Momentum-resolved STM studies of Rashba-split surface states on the topological semimetal Sb 

      Soumyanarayanan, Anjan; Hoffman, Jennifer Eve (Elsevier BV, 2014)
      Topological materials host protected surface states with locked spin and momentum degrees of freedom. The helical Dirac character of the surface states, of tremendous scientific interest, stems from the interplay of the ...
    • Monolayer FeSe on SrTiO3 

      Huang, Dennis; Hoffman, Jennifer Eve (Annual Reviews, 2017)
      Epitaxial engineering of solid-state heterointerfaces is a leading avenue to realizing enhanced or novel electronic states of matter. As a recent example, bulk FeSe is an unconventional superconductor with a modest transition ...
    • Nanopatterning and Transport Properties of Cuprate Superconductors 

      Litombe, Nicholas E. (2015-05-19)
      Almost 30 years since the discovery of the copper oxide high temperature superconductors, the underlying mechanism describing their behavior continues to elude experimentalists and theorists alike. Understanding the ...
    • Nanoscale Imaging and Control of Resistance Switching in VO[sub]2 at Room Temperature 

      Kim, Jeehoon; Ko, Changhyun; Frenzel, Alex James; Ramanathan, Shriram; Hoffman, Jenny Eve (American Institute of Physics, 2010)
      We demonstrate controlled local phase switching of a VO[sub]2 film using a biased conducting atomic force microscope tip. After application of an initial, higher ‘training’ voltage, the resistance transition is hysteretic ...
    • Nanoscale Imaging of Phase Transitions with Scanning Force Microscopy 

      Pivonka, Adam (2012-10-31)
      Nanoscale imaging of materials through phase transitions can provide valuable insight into the local nature of the transition and the emergence of order. The scanning force microscope used in the studies presented here is ...
    • Nanoscale Interplay of Strain and Doping in a High-Temperature Superconductor 

      Zeljkovic, Ilija; Nieminen, Jouko; Huang, Dennis; Chang, Tay-Rong; He, Yang; Jeng, Horng-Tay; Xu, Zhijun; Wen, Jinsheng; Gu, Genda; Lin, Hsin; Markiewicz, Robert S.; Bansil, Arun; Hoffman, Jennifer Eve (American Chemical Society (ACS), 2014)
      The highest-temperature superconductors are electronically inhomogeneous at the nanoscale, suggesting the existence of a local variable that could be harnessed to enhance the superconducting pairing. Here we report the ...