Bright upconverted emission from light-induced inelastic tunneling

Eradzh Rakhmatov; Amirhossein Alizadehkhaledi; Ghazal Hajisalem; Reuven Gordon

doi:10.1364/oe.390130

Inelastic tunneling spectroscopy of magnetic tunnel junctions based on CoFeB∕MgO∕CoFeB with Mg insertion layer

Journal of Applied Physics ◽

10.1063/1.2162047 ◽

2006 ◽

Vol 99 (8) ◽

pp. 08T305 ◽

Cited By ~ 62

Author(s):

Guo-Xing Miao ◽

Krishna B. Chetry ◽

Arunava Gupta ◽

William H. Butler ◽

Koji Tsunekawa ◽

...

Keyword(s):

Tunnel Junctions ◽

Magnetic Tunnel Junctions ◽

Tunneling Spectroscopy ◽

Inelastic Tunneling

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Chemical identification and manipulation of molecules by vibrational excitation via inelastic tunneling process with scanning tunneling microscopy

Progress in Surface Science ◽

10.1016/j.progsurf.2005.05.001 ◽

2005 ◽

Vol 78 (2) ◽

pp. 41-85 ◽

Cited By ~ 97

Author(s):

Tadahiro Komeda

Keyword(s):

Scanning Tunneling Microscopy ◽

Vibrational Excitation ◽

Scanning Tunneling ◽

Chemical Identification ◽

Tunneling Microscopy ◽

Tunneling Process ◽

Inelastic Tunneling

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VIBRATIONAL SPECTROSCOPY OF CO/Cu(211) WITH A CO TERMINATED TIP

Modern Physics Letters B ◽

10.1142/s0217984999000890 ◽

1999 ◽

Vol 13 (20) ◽

pp. 709-715 ◽

Cited By ~ 26

Author(s):

FRANCESCA MORESCO ◽

GERHARD MEYER ◽

KARL HEINZ RIEDER

Keyword(s):

Vibrational Spectroscopy ◽

Scanning Tunneling Microscope ◽

Scanning Tunneling ◽

Rotational Mode ◽

Tunneling Microscope ◽

Vibrational Excitations ◽

Translational Mode ◽

Inelastic Tunneling ◽

Open Question ◽

First Time

Vibrational excitations of an isolated CO molecule adsorbed on a Cu(211) surface have been, for the first time, observed with a CO terminated scanning tunneling microscope tip. Both the frustrated translational and rotational modes were observed, and in agreement with the case of a metallic tip. The presence of a CO molecule on the tip, transferred by controlled vertical manipulation, strongly influences the frustrated translational mode of the CO molecule, while it does not affect the frustrated rotational mode. The present work demonstrates that scanning tunneling vibrational spectroscopy is also possible with a molecule at the end of the tip, opening new interesting fields of research and putting some more light on the still open question of inelastic tunneling and its selection rules.

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Magnetism and Spin Tunneling in Nanostructures

MRS Proceedings ◽

10.1557/proc-491-117 ◽

1997 ◽

Vol 491 ◽

Author(s):

Alexander Bratkovsky

Keyword(s):

Spin Polarization ◽

Tunnel Junctions ◽

Iron Group ◽

Defect States ◽

Resistance Change ◽

Half Metallic ◽

Spin Tunneling ◽

Inelastic Tunneling ◽

Resonant Tunnel ◽

General Method

ABSTRACTIn the present paper different tunneling mechanisms in conventional and half-metallic ferromagnetic tunnel junctions are analyzed within the same general method. Theoretically calculated direct tunneling in iron group systems leads to about a 30% change in resistance, which is close but lower than experimentally observed values. It is shown that the larger observed values of the TMR might be a result of tunneling involving surface polarized states. We find that tunneling via resonant defect states in the barrier radically decreases the TMR (down to 4% with Fe-based electrodes), and a resonant tunnel diode structure would give a TMR of about 8%. With regards to inelastic tunneling, magnons and phonons exhibit opposite effects: one-magnon emission generally results in spin mixing and, consequently, reduces the TMR, whereas phonons are shown to enhance the TMR. The inclusion of both magnons and phonons reasonably explains an unusual bias dependence of the TMR.The model presented here is applied qualitatively to half-metallics with 100% spin polarization, where one-magnon processes are suppressed and the change in resistance in the absence of spin-mixing on impurities may be arbitrarily large. Even in the case of imperfect magnetic configurations, the resistance change can be a few 1000 percent. Examples of half-metallic systems are CrO2/TiO2 and CrO2/RuO2, and an account of their peculiar band structures is presented. The implications and relation of these systems to CMR materials, which are nearly half-metallic, are discussed.

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