Two-Electron Photon Emission from Metallic Quantum Wells

Hoffmann, Germar; Berndt, Richard; Johansson, Peter

doi:10.1103/physrevlett.90.046803

Cited by 50 publications

(31 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The up-conversion luminescence observed for phthalocyanine has been interpreted as originating from a triplet-triplet annihilation process [45,177]. For the data reported by Liu et al, the energy forbidden light emission was tentatively interpreted as a two-electron process, similar to the mechanism proposed for sodium quantum well states [135], see Section 4.1.4. A mechanism involving the resonant plasmon emission in the nanocavity formed by sample and tip is proposed for the up-conversion luminescence observed in Ref.…”

Section: Molecular Multilayersmentioning

confidence: 77%

“…Subsequently, the emission of photons with energies exceeding the energy of the tunneling electrons has been observed for the same system. This surprising phenomenon has been modeled by a two-electron process, similar to an Auger decay, which leads to quantum well transitions [135].…”

Section: Recent Developmentsmentioning

confidence: 99%

“…The authors are able to analyze the experimental data in terms of plasmon excitation for the single electron processes and of hot-hole processes for the observed two electron photon emission, where in the latter case the energy of the light emission was found to be higher than the tunneling voltage (as in Ref. [135], where an Auger-like process has been proposed. In the present case a hot-electron-hole cascade mechanism has been invoked.)…”

Section: Recent Developmentsmentioning

confidence: 99%

See 2 more Smart Citations

Luminescence experiments on supported molecules with the scanning tunneling microscope

Rossel

Pivetta

Schneider

2010

Surface Science Reports

111

115

View full text Add to dashboard Cite

Section: Molecular Multilayersmentioning

confidence: 77%

Section: Recent Developmentsmentioning

confidence: 99%

Section: Recent Developmentsmentioning

confidence: 99%

See 1 more Smart Citation

Luminescence experiments on supported molecules with the scanning tunneling microscope

Rossel

Pivetta

Schneider

2010

Surface Science Reports

111

115

View full text Add to dashboard Cite

“…Photon energies exceeding eV indicate that hot carriers are involved. [10][11][12] For simplicity, we refer to this emission as 2e light.…”

Section: Introductionmentioning

confidence: 99%

Hot electron cascades in the scanning tunneling microscope

2013

Self Cite

View full text Add to dashboard Cite

The nonequilibrium distribution of electrons at the junction of a scanning tunneling microscope is investigated by detecting photons with energies hν > eV , where V is the bias voltage. Electrons are found at energies exceeding the Fermi level by almost eV . While their distribution deviates from a Fermi-Dirac function it is consistent with a model of hot electrons and holes that diffuse in energy and real space.

show abstract

“…This picture has been confirmed in numerous experimental [3] and theoretical [4] studies. However, a closer look at some experiments [5][6][7] reveals the unexpected feature that, in addition, light with energy ω > eV is emitted that shows a spectrum which is also reminiscent of the SPP modes. Using energy considerations, such a process can be attributed to two simultaneously tunneling electrons providing enough energy to explain the observation of over-bias emission.…”

mentioning

confidence: 99%

Overbias Light Emission due to Higher-Order Quantum Noise in a Tunnel Junction

Holmqvist

Belzig

2014

Phys. Rev. Lett.

View full text Add to dashboard Cite

Understanding tunneling from an atomically sharp tip to a metallic surface requires to account for interactions on a nanoscopic scale. Inelastic tunneling of electrons generates emission of photons, whose energies intuitively should be limited by the applied bias voltage. However, experiments [Phys. Rev. Lett. 102, 057401 (2009)] indicate that more complex processes involving the interaction of electrons with plasmon polaritons lead to photon emission characterized by over-bias energies. We propose a model of this observation in analogy to the dynamical Coulomb blockade, originally developed for treating the electronic environment in mesoscopic circuits. We explain the experimental finding quantitatively by the correlated tunneling of two electrons interacting with an LRC circuit modeling the local plasmon-polariton mode. To explain the over-bias emission, the non-Gaussian statistics of the tunneling dynamics of the electrons is essential.PACS numbers: 73.23. Hk, 73.20.Mf, 68.37.Ef, 72.70.+m Light emission of electrons tunneling from a scanning tunneling microscope (STM) to a metallic surface has already been studied for many years [1]. The basic mechanism leading to light emission has been identified as the interaction of the tunneling electrons with a localized surface plasmon-polariton (SPP) mode [2]. Considering such a mechanism in a simple picture shows that the emitted light spectrum is limited in frequency by the bias voltage according to ω < eV . This is a simple consequence of the presence of Fermi seas in the electronic leads, which prohibits inelastic tunneling transitions with higher energy exchange due to the Pauli principle. The SPP resonance, which is finally responsible for the photon emission, acts as a frequency filter and hence the measured spectrum is essentially the SPP resonance cut off at a frequency eV / . This picture has been confirmed in numerous experimental [3] and theoretical [4] studies. However, a closer look at some experiments [5][6][7] reveals the unexpected feature that, in addition, light with energy ω > eV is emitted that shows a spectrum which is also reminiscent of the SPP modes. Using energy considerations, such a process can be attributed to two simultaneously tunneling electrons providing enough energy to explain the observation of over-bias emission. However, why the electrons tunnel in a correlated manner remains speculative. A possible explanation is a hot electron distribution created by an effective electron-electron interaction [8,9], which however has been not experimentally tested yet.In this Letter, we will develop an alternative approach based on the idea that on a short time scale multielectron coherent processes appear at a tunnel junction. In a coherent two-electron tunneling process where each electron gives contributes an energy eV an excitation of an overbias plasmon resonance via a virtual state can be created. The SPP mode finally leads to the over-bias light in a standard emission process. Essentially in our model the coupled electron-SPP system h...

show abstract

Two-Electron Photon Emission from Metallic Quantum Wells

Cited by 50 publications

References 22 publications

Luminescence experiments on supported molecules with the scanning tunneling microscope

Luminescence experiments on supported molecules with the scanning tunneling microscope

Hot electron cascades in the scanning tunneling microscope

Overbias Light Emission due to Higher-Order Quantum Noise in a Tunnel Junction

Contact Info

Product

Resources

About