Dimensional Crossover at the Superconductor-Insulator Transition

  • Scientists watch 2D puddles of electrons spontaneously emerge in a 3D superconducting material
  • Signatures of two-dimensional superconductivity emerging within a three-dimensional host superconductor

  • 2D superconductor

    Probing Many-body Physics in Quantum Engineered Kondo Lattices

    Kondo Lattice

    Optoelectronic crystal of MoS2 artificial atoms



    Two exotic forms of carbon crafted into a molecule for steering electron flow.

    Buckydiamondoids1 Buckydiamondoids2 Buckydiamondoids3

    Molecular Graphene

    Molecular Graphene

    Electronic Quantum Holography

    Jay Leno

    The Tonight Show. Jay Leno explains the quantum hologram. (Air date: Friday, February 6, 2009). Image credit: NBC.

    Images (click for full size)

    Holographic projection

    Writing with electrons. Atomically precise molecular holograms (bottom topograph) are fashioned with scanning tunneling microscope manipulation. When illuminated by the resident two-dimensional (2D) electron gas confined to the surface (wave patterns), a three-dimensional (3D) holographic projection is created, localized in the central purple region devoid of molecules. Information, here in the form of simple letters, is densely and volumetrically encoded in this region and then read out by scanning tunneling spectroscopy. Here, two pages of information are retrieved (red and blue letters) from the data cube (white lines). In analogy to optical holography, these electronic objects correspond to the 3D objects commonly projected from 2D optical holograms. However, due to the quantum nature of the electron states used, these electronic objects have features smaller than anything possible to construct directly with atoms. The information density limit of discrete matter identified with atomic manipulation is here surpassed by showing that electrons are capable of subatomic encoding. Image credit: Hari Manoharan / Stanford University.

    Quantum holography concept

    Electronic quantum holography concept. [Left] In traditional optical holography, light shone on a 2D hologram projects a 3D object viewable by eye (a density of mass). [Right] In this work, two-dimensional quantum electrons illuminate coplanar holograms assembled with atomic manipulation. The analogous projection is an object of electron density of quantum states, which is observed via scanning tunnelling microscopy. This projection is into one energetic and two spatial dimensions, spanning a 3D space into which information can be densely holographically encoded. Image credit: Hari Manoharan / Stanford University.

    Holographically embedded S and U

    Volumetric quantum holography: stacking two data pages in the same physical space. The electronic object projected by a hologram is shown as a translucent gray curtain in position-energy space. Slices through the object at specific energies reveal the encoded letters S and U. Image credit: Hari Manoharan / Stanford University.

    Subatomic quantum holography

    Subatomic quantum holography: surpassing the atomic limit of information density. At high energies, the size of electron waves diminishes, allowing electronic features that are smaller than those created with atomic matter. The bits that this high-energy electronic S represents are packed more densely than the invisible underlying atoms. Image credit: Hari Manoharan / Stanford University.

    Quantum holography research team

    Electronic quantum holography research team. Chris Moon (physics Ph.D. student), Prof. Hari Manoharan (team leader), and Laila Mattos (physics Ph.D. student) are three scientists who worked on the subatomic writing project.
    TIFF originals [Color | BW | CMYK]
    Image credit: L. A. Cicero / Stanford News Service.

    Hari Manoharan

    Prof. Hari Manoharan.
    TIFF originals [Color | BW | CMYK]
    Image credit: L. A. Cicero / Stanford News Service.

    Movies (click to play)

    Holographic readout

    Full holographic readout. Holographic projections into position-energy space are read out by mapping the 2D electron wavefunctions in a range of energies. Images at particular energies reveal encoded patterns in the electron density. [QuickTime, 408 KB]

    Quantum Phase via Geometry

    Press release: Stanford Researchers Hear the Sound of Quantum Drums

    Links to Summary and Paper at Science magazine.

    Images of quantum drums:
    (Click image for full TIFF version)

    Quantum Shape Shifting

    Quantum shape shifting. Molecular nanostructures of different shape (top and bottom surfaces), linked topologically (beam) to share the same spectrum, enable the measurement of quantum mechanical phase. Background: color-encoded quantum state transplantation matrix.

    Topographical Structure Topographical Structure

    A wrinkle in space. Two quantum nanostructures of different shape (top and bottom surfaces) can be linked topologically to sound the same, enabling the measurement of quantum mechanical phase (background).

    Assembly of isospectral structure Assembly of isospectral structure

    Nanoassembly of quantum drums enables measurement of quantum mechanical phase. Background: color-encoded quantum state transplantation matrix.

    Two isospectral structures and one nonisospectral structure

    Geometry over interferometry. Geometric tuning of quantum materials enables the measurement of normally forbidden quantum mechanical phase information.

    Movies and sounds of quantum drums:

    Quantum Isospectrality

    Quantum isospectrality. Sounds generated from the average spectra acquired inside the Bilby, Hawk, and Broken Hawk shapes. Each sound is repeated 8 times as the topograph of the corresponding quantum drum is highlighted. Bilby and Hawk which are isospectral sound the same, while Broken Hawk can be audibly distinguished.

    Movie S1 - [QuickTime, 1.8 MB]

    Quantum homophonicity

    Quantum homophonicity. Audio conversion of 3 pairs of point spectra acquired within the isospectral Aye-aye and Beluga shapes. The similarity between the homophonic points is audibly contrasted with the easily discernable differences between other points. Each sound is repeated 4 times as the topograph of the corresponding nanostructure is highlighted and the position of the acquired spectrum is identified with a red cross.

    Movie S2 - [QuickTime, 3.8 MB]

    Quantum transplantation

    Quantum transplantation. Full phase extraction process for modes 1 to 3 of the Aye-aye (A) and Beluga (B) quantum resonators. The algorithm is represented by a black box, the quantum transplantation machine (QTM), which has the goal of obtaining the full wave functions including all amplitude and phase information. Chapter headings, matching audio narration, can be selected to jump to specific QTM states.

    Movie S3 - [QuickTime, 16.1 MB]

    Previous press selections

    January 2006: The 7:30 Report (Australian Broadcasting Corporation)

    Scientists Don't Doubt Nano Future

    June 2005: Stanford Magazine


    May 2004: IndoLink

    Hari Manoharan's Nanotechnology Breakthrough

    November 2002: Physics World

    Iconic Images: Quantum Mirage

    September 2002: The Osgood File (CBS Radio Network)

    Atom Sounds

    Media Images

    New York Times compositeNew ScientistcuHalliday and Resnick coverUS NewsNanotechnology Law cover
    Nature Nanotech June 15 2001Korean DailIBM Journal of Research and DevelopmentCuPhysics News 1999 CuPhysics Web Quantum Mirage