H. Grube

National Institute of Standards and Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

J. M. Pomeroy

National Institute of Standards and Technology

A. C. Perrella

McMaster University

J. D. Gillaspy

National Institute of Standards and Technology

John J. Boland

Trinity College Dublin

Geoffrey W. Brown

Los Alamos National Laboratory

Steven R. Schofield

University College London

Marilyn E. Hawley

Los Alamos National Laboratory

Neil J. Curson

London Centre for Nanotechnology

M. Y. Simmons

UNSW Sydney

Robert G. Clark

Australian National University

Cooperative Institutions

National Institute of Standards and Technology

Los Alamos National Laboratory

University of North Carolina at Chapel Hill

Lawrence Livermore National Laboratory

North Carolina State University

Los Alamos Medical Center

Cornell University

Astronomy and Space

Johns Hopkins University

National Institute of Standards

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Magnetoresistance based first-order reversal curve analysis of magnetic tunnel junctions

Applied Physics Letters (2009)

J. M. Pomeroy Theodore C. White H. Grube J. C. Read Joseph E. Davies

First-order reversal curve (FORC) analysis is conventionally applied to magnetization versus applied magnetic field loops to determine the ensemble properties of multidomain magnetic samples ranging from naturally occurring geological samples to exquisitely engineered materials for use in magnetic storage. We apply FORC analysis to magnetic tunnel junctions (MTJs) by using magnetoresistance instead of magnetization field. By using the MTJ resistance to monitor domain switching, arbitrarily small samples can be studied, as well as functioning devices after lithographic patterning. Experimental data are presented from sub-0.01 mm2 MTJs that illustrate the application of FORC analysis and demonstrate asymmetric switching distributions when mapped in coercive versus interaction field space.

Tunnel magnetoresistance

Magnetic storage

Magnetization reversal

Single domain

Iron alloys

Domain wall (magnetism)

10.1063/1.3175723

Cite

Citations (11)

Imaging Charged Defects on Clean Si(100)-(2x1) with Scanning Tunneling Microscopy

APS (2002)

Geoffrey W. Brown H. Grube M. E. Hawley Steven R. Schofield Neil J. Curson

Source

Cite

Citations (0)

Simultaneous atomic force microscopy measurement of topography and contact resistance of metal films and carbon nanotubes

Carolina Digital Repository (University of North Carolina at Chapel Hill) (2003)

Michael Stadermann H. Grube John J. Boland S. J. Papadakis M. R. Falvo

Contact resistance

10.17615/9thb-7d49

Cite

Citations (1)

Transport and STM measurements of HCI modified materials

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms (2007)

J. M. Pomeroy H. Grube A. C. Perrella C. E. Sosolik J. D. Gillaspy

10.1016/j.nimb.2006.12.019

Cite

Citations (3)

Scanning tunneling microscopy imaging of charged defects on clean Si(100)-(2×1)

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films (2003)

Geoffrey W. Brown H. Grube M. E. Hawley Steven R. Schofield Neil J. Curson

We have used scanning tunneling microscopy (STM) to image charged defects on the clean (100)-(2×1) surface of p-type silicon. In the absence of “C”-type defects, band bending can occur during STM imaging, allowing near surface charge to influence the state density contributing to the tunnel current. As in the case of cleavage faces of III–V semiconductor crystals, the charge-induced band bending produces long range enhancements superimposed on the periodic surface lattice. The charged defects observed in this work are of the types commonly observed elsewhere in clean Si(100)-(2×1) STM studies, however, not all defects of a given type appear charged. This would indicate subtle differences in defect structure that are not obvious at higher sample bias. This work demonstrates the ability to observe charged features on the clean Si(100) surface, which will be important for current and future research focused on producing atomic scale electronic structures.

Band bending

Cleavage (geology)

10.1116/1.1566973

Cite

Citations (13)

Highly Charged Ion Modified Magnetic Tunnel Junctions

MRS Proceedings (2006)

H. Grube J. M. Pomeroy A. C. Perrella J. D. Gillaspy

Tunnel magnetoresistance

10.1557/proc-0960-n08-02

Cite

Citations (1)

Observation of substitutional and interstitial phosphorus on cleanSi(100)−(2×1)with scanning tunneling microscopy

Physical Review B (2005)

Geoffrey W. Brown Blas P. Uberuaga H. Grube Marilyn E. Hawley Steven R. Schofield

We have used scanning tunneling microscopy to identify phosphorus that is present at the clean silicon $(100)\text{\ensuremath{-}}(2\ifmmode\times\else\texttimes\fi{}1)$ surface as a result of the thermal cycling necessary for preparation of samples cut from heavily doped wafers. Substitutional phosphorus is observed in top layer sites as buckled $\mathrm{Si}\text{\ensuremath{-}}\mathrm{P}$ heterodimers. We also observe a second type of feature that appears as a single depressed dimer site. Within this site, the atoms appear as a pair of protrusions in the empty states and a single protrusion in the filled states. These properties are not consistent with known adsorbate signatures or previously reported observations of $\mathrm{P}\text{\ensuremath{-}}\mathrm{P}$ dimers on the $(100)\text{\ensuremath{-}}(2\ifmmode\times\else\texttimes\fi{}1)$ surface. The lack of other impurity sources suggests that they are due to either phosphorus or silicon. The symmetry of the features and their magnitude are consistent with one of those elements residing in an interstitial site just below the top layer of atoms. To identify the type of interstitial, we performed density functional theory calculations for both phosphorus and silicon located below a surface dimer. The resulting charge density plots and simulated STM images are consistent with interstitial phosphorus and not interstitial silicon.

10.1103/physrevb.72.195323

Cite

Citations (11)

Erratum: “Magnetoresistance based first-order reversal curve analysis of magnetic tunnel junctions” [Appl. Phys. Lett. 95, 022514 (2009)]

Applied Physics Letters (2010)

J. M. Pomeroy TA White H. Grube J. C. Read J. E. Davies

First Page

Tunnel magnetoresistance

10.1063/1.3291522

Cite

Citations (0)

Origin of homoepitaxial faulted island growth on the Si(111) surface