Interface-engineered electron and hole tunneling

Although the phenomenon of tunneling has been known since the advent of quantum mechanics, it continues to enrich our understanding of many fields of science. Commonly, this effect is described in terms of electrons traversing the potential barrier that exceeds their kinetic energy due to the wave nature of electrons. This picture of electron tunneling fails, however, for tunnel junctions, where the Fermi energy lies sufficiently close to the insulator valence band, in which case, hole tunneling dominates. We demonstrate the deterministic control of electron and hole tunneling in interface-engineered Pt/BaTiO3/La0.7Sr0.3MnO3 ferroelectric tunnel junctions by reversal of tunneling electroresistance. Our electrical measurements, electron microscopy and spectroscopy characterization, and theoretical modeling unambiguously point out to electron or hole tunneling regimes depending on interface termination. The interface control of the tunneling regime offers designed functionalities of electronic devices.

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Ultrahigh-Vacuum Electron Microscopy for Gold Nanostructures

Microscopy and Microanalysis ◽

10.1017/s1431927600030671 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 920-921

Author(s):

Yukihito Kondo ◽

Kimiharu Okamoto ◽

Mikio Naruse ◽

Toshikazu Honda ◽

Mike Kersker

Keyword(s):

Electron Microscopy ◽

Field Emission ◽

Electronic Devices ◽

Ultrahigh Vacuum ◽

Gold Nanostructures ◽

Scanning Tunneling ◽

Nano Scale ◽

Transmission Electron ◽

Column Type ◽

Schottky Type

Ultrahigh-vacuum transmission electron microscopy (UHVTEM) has become increasingly popular for the direct observation of nanostructures having clean surfaces, since industrial requirements to make and research nano-scale materials have been rapidly growing for quantum or nanoscale electronic devices. Since we have first developed high resolution UHVTEM in 1986, the UHVTEMs have been evolved with steady advances such as UHV compatible goniometer, field emission gun or etc. Furthermore, the UHVTEM started to combine analytical capabilities such as energy dispersive X-ray spectrometer, in-column type energy filter and etc., and to combine STM (scanning tunneling microscope). The UHV technology is essential for the analysis, because the portion of contaminant in a nano-scale specimen increases as the size of the specimen goes down. This paper reports the results of gold nanostructures by recently the developed UHVTEM.Figure 1 shows recently developed UHVTEM with Schottky type field emission gun.

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Influence of inhomogeneity on correlated single-electron tunneling in one-dimensional array of small tunnel junctions

Physica B Condensed Matter ◽

10.1016/0921-4526(94)90984-9 ◽

1994 ◽

Vol 194-196 ◽

pp. 1309-1310 ◽

Cited By ~ 1

Author(s):

N. Yoshikawa ◽

K. Fukushima ◽

M. Sugahara

Keyword(s):

Tunnel Junctions ◽

Electron Tunneling ◽

Single Electron ◽

One Dimensional ◽

Dimensional Array ◽

Single Electron Tunneling

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Scanning Transmission Electron Microscopy Investigation of the Structure of Multilayered Perpendicular Magnetic Tunnel Junctions

Microscopy and Microanalysis ◽

10.1017/s1431927615004882 ◽

2015 ◽

Vol 21 (S3) ◽

pp. 817-818

Author(s):

Danielle Reifsnyder Hickey ◽

K. Andre Mkhoyan

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Tunnel Junctions ◽

Transmission Electron Microscopy Investigation ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Microscopy Investigation ◽

Electron Microscopy Investigation ◽

Scanning Transmission

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Growth of epitaxial ZnO films on Si(111)

MRS Proceedings ◽

10.1557/proc-722-k10.7 ◽

2002 ◽

Vol 722 ◽

Cited By ~ 2

Author(s):

Chunming Jin ◽

Ashutosh Tiwari ◽

A. Kvit ◽

J. Narayan

Keyword(s):

Electron Microscopy ◽

Transparent Conducting Oxide ◽

Deposition Process ◽

Growth Direction ◽

Zno Films ◽

X Ray Diffraction ◽

Electrical Measurements ◽

X Ray ◽

Transmission Electron ◽

Aln Buffer

AbstractEpitaxial ZnO films have been grown on Si(111) substrates by employing a AlN buffer layer during a pulsed laser-deposition process. The epitaxial structure of AlN on Si(111) substrate provides a template for ZnO growth. The resultant films are evaluated by transmission electron microscopy, x-ray diffraction, and electrical measurements. The results of x-ray diffraction and electron microscopy on these films clearly show the epitaxial growth of ZnO films with an orientational relationship of ZnO[0001]||Aln[0001]||Si[111] along the growth direction and ZnO[2 11 0]||AlN[2 11 0]||Si[0 11] along the in-plane direction. High electrical conductivity (103 S/m at 300 K) and a linear I-V characteristics make these epitaxial films ideal for microelectronic, optoelectronic, and transparent conducting oxide applications.

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Inelastic electron tunneling spectroscopy measurements using adjustable oxide-free tunnel junctions

Review of Scientific Instruments ◽

10.1063/1.1347382 ◽

2001 ◽

Vol 72 (3) ◽

pp. 1781 ◽

Cited By ~ 8

Author(s):

Darin T. Zimmerman ◽

Glenn Agnolet

Keyword(s):

Tunnel Junctions ◽

Electron Tunneling ◽

Tunneling Spectroscopy ◽

Inelastic Electron ◽

Inelastic Electron Tunneling Spectroscopy ◽

Inelastic Electron Tunneling ◽

Electron Tunneling Spectroscopy

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KINETIC ENERGY DRIVEN SUPERCONDUCTIVITY AND SUPERFLUIDITY

Modern Physics Letters B ◽

10.1142/s0217984911027613 ◽

2011 ◽

Vol 25 (29) ◽

pp. 2219-2237 ◽

Cited By ~ 12

Author(s):

J. E. HIRSCH

Keyword(s):

Thermal Expansion ◽

Quantum Mechanics ◽

Kinetic Energy ◽

Superfluid Helium ◽

Negative Charge ◽

Negative Thermal Expansion ◽

Zero Point ◽

Meissner Effect ◽

Helium 4 ◽

Λ Point

The theory of hole superconductivity proposes that superconductivity is driven by lowering of quantum kinetic energy and is associated with expansion of electronic orbits and expulsion of negative charge from the interior to the surface of superconductors and beyond. This physics provides a dynamical explanation of the Meissner effect. Here we propose that similar physics takes place in superfluid helium 4. Experimental manifestations of this physics in 4 He are the negative thermal expansion of 4 He below the λ point and the "Onnes effect", the fact that superfluid helium will creep up the walls of the container and escape to the exterior. The Onnes effect and the Meissner effect are proposed to originate in macroscopic zero point rotational motion of the superfluids. It is proposed that this physics indicates a fundamental inadequacy of conventional quantum mechanics.

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