The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform

Stephen Klassen - One of the best experts on this subject based on the ideXlab platform.

  • Portrayal of the History of the Photoelectric Effect in Laboratory Instructions
    Science & Education, 2012
    Co-Authors: Stephen Klassen, Mansoor Niaz, Don Metz, Barbara Mcmillan, Sarah Dietrich
    Abstract:

    The literature on the pedagogical aspects of the Photoelectric Effect as used in the undergraduate student laboratory shows that little research has been done in this area. Our current study is an analysis of the instructions in 38, electronically published laboratory manuals for the Photoelectric Effect. The analyses were based on history and philosophy of science criteria that we had developed for evaluating the presentation of the Photoelectric Effect in introductory, university-physics textbooks. The results show that writers of laboratory instructions do not pay sufficient attention to the relevant background for the Photoelectric Effect. In our study, none of the instructions achieved a score of excellent, only 5% were scored as satisfactory, and only 7% mentioned the various aspects contained in our criteria. These results for our analysis of laboratory instructions are significantly less favorable than those achieved for physics textbooks in our previous study. Based on our work, we recommend that several historical aspects be included in all laboratory instructions for the Photoelectric Effect.

  • The Photoelectric Effect: Reconstructing the Story for the Physics Classroom
    Science Education, 2009
    Co-Authors: Stephen Klassen
    Abstract:

    The Photoelectric Effect is commonly used as the introductory topic for the study of quantum physics. However, a literature review reveals that besides various weaknesses and errors in the presentation of the history of the Photoelectric Effect, textbook presentations also contain incorrect presentations of the work function and the photon concept. In this paper, I present, in story form, five key episodes of the history of the Photoelectric Effect that are necessary for its accurate and adequate portrayal: (a) the discovery of the Photoelectric Effect, (b) the characterization of and initial explanation for the Photoelectric Effect, (c) Einstein’s revolutionary paper on the light quantum and its explanation for the Photoelectric Effect, and his, eventually, receiving the Nobel Prize despite not having his hypothesis accepted, (d) Millikan’s experimental verification of Einstein’s Photoelectric equation despite not accepting Einstein’s hypothesis, and (e) Compton’s measurements and his theoretical explanation which produced the ultimate acceptance of Einstein’s hypothesis. The story, entitled “The Birth of the Photon Concept,” has been tested in a classroom setting and is proposed as an essential component in the process of developing sound instructional materials.

  • The Photoelectric Effect: Rehabilitating the Story for the Physics Classroom
    2008
    Co-Authors: Stephen Klassen
    Abstract:

    The Photoelectric Effect is commonly used as the introductory topic for the study of quantum physics. However, there are various indicators that some instructional materials and approaches to the topic contain deficiencies and even factual errors. A major aspect of instruction is the historical and scientific background for the Photoelectric Effect. In this paper, I outline the key elements of the history of the discovery of the Photoelectric Effect, of Einstein's light-quantum theory, and of the ultimate acceptance of the theory that are necessary for developing sound instructional materials.

Markku Räsänen - One of the best experts on this subject based on the ideXlab platform.

  • Experimental observation of two-photon Photoelectric Effect from silver aerosol nanoparticles
    New Journal of Physics, 2007
    Co-Authors: Mikko Sipilä, A.a. Lushnikov, Leonid Khriachtchev, Markku Kulmala, Heikki Tervahattu, Markku Räsänen
    Abstract:

    We report on the observation of two-photon electron emission from silver nanoparticles suspended in nitrogen flow resulting from irradiating them with continuous wave and pulsed laser light with photon energies below the threshold of the single-photon Photoelectric Effect. The photoelectron yield is quadratic in the light intensity, and the two-photon electron emission threshold is evident. The efficiency of the two-photon Photoelectric Effect is determined for nanoparticles of various sizes. These experiments offer the net information on nonlinear quantum properties of an isolated single nanoparticle which is crucial for developing theoretical models.

Bing-hong Wang - One of the best experts on this subject based on the ideXlab platform.

  • Photoelectric Effect in the presence of a bichromatic laser field
    Journal of Physics B: Atomic Molecular and Optical Physics, 2010
    Co-Authors: Liang Bai, Bing-hong Wang
    Abstract:

    Photoelectric Effect in atomic hydrogen in the presence of bichromatic laser fields composed of a fundamental frequency and its second or third harmonics is investigated. The expression of the S-matrix for the laser-assisted Photoelectric Effect is derived in the length gauge, which can simplify the elements of the matrix. A general dressed wavefunction of the atom is derived in perturbation theory. The continuum state of the ejected electron is described by a Coulomb–Volkov wavefunction. Numerical results of photoionization cross section for the distinct second component are obtained and compared with the monochromatic field dressing case. It is shown that the photoionization cross section is modified notably by introducing the second component of field, especially when the colliding system absorbs or emits a considerable number of laser photons.

F Parmigiani - One of the best experts on this subject based on the ideXlab platform.

  • evidence of vectorial Photoelectric Effect on copper
    arXiv: Materials Science, 2012
    Co-Authors: Emanuele Pedersoli, Francesco Banfi, B Ressel, S Pagliara, Claudio Giannetti, Gianluca Galimberti, S Lidia, John Corlett, Gabriele Ferrini, F Parmigiani
    Abstract:

    Quantum Efficiency (QE) measurements of single photon photoemission from a Cu(111) single crystal and a Cu polycrystal photocathodes, irradiated by 150 fs-6.28 eV laser pulses, are reported over a broad range of incidence angle, both in s and p polarizations. The maximum QE (\simeq 4\times10^{-4}) for polycrystalline Cu is obtained in p polarization at an angle of incidence {\theta} = 65deg. We observe a QE enhancement in p polarization which can not be explained in terms of optical absorption, a phenomenon known as vectorial Photoelectric Effect. Issues concerning surface roughness and symmetry considerations are addressed. An explanation in terms of non local conductivity tensor is proposed.

  • evidence of vectorial Photoelectric Effect on copper
    Applied Physics Letters, 2005
    Co-Authors: Emanuele Pedersoli, Francesco Banfi, B Ressel, S Pagliara, Claudio Giannetti, Gianluca Galimberti, S Lidia, John Corlett, Gabriele Ferrini, F Parmigiani
    Abstract:

    Quantum Efficiency (QE) measurements of single photon photoemission from a Cu(111) single crystal and a Cu polycrystal photocathodes, irradiated by 150 fs-6.28 eV laser pulses, are reported over a broad range of incidence angle, both in s and p polarizations. The maximum QE (approx. = 4x10-4) for polycrystalline Cu is obtained in p polarization at an angle of incidence theta = 65 deg. We observe a QE enhancement in p polarization which can not be explained in terms of optical absorption, a phenomenon known as vectorial Photoelectric Effect. Issues concerning surface roughness and symmetry considerations are addressed. An explanation in terms of non local conductivity tensor is proposed.

Majed Chergui - One of the best experts on this subject based on the ideXlab platform.

  • laser assisted Photoelectric Effect from liquids
    Physical Review Letters, 2016
    Co-Authors: Christopher Arrell, J Ojeda, Lars Mewes, Jakob Grilj, Fabio Frassetto, Luca Poletto, F Van Mourik, Majed Chergui
    Abstract:

    The laser-assisted Photoelectric Effect from liquid surfaces is reported for the first time. Photoelectrons generated by 35.6 eV radiation from a liquid microjet of water under vacuum are dressed with a ℏω=1.55  eV laser field. The subsequent redistribution of the photoelectron energies consists in the appearance of sidebands shifted by energies equivalent to ℏω, 2ℏω, and 3ℏω. The response has been modeled to the third order and combined with energy-resolved measurements. This result opens the possibility to investigate the dynamics at surfaces of liquid solutions and provide information about the electron emission process from a liquid.