The linear photon-drag effect was extensively studied in the 70s, first by Grinberg [1] and right afterwards by Gibson and others [2-4]. In his paper, Grinberg states: “In the absorption of light by free carriers, the momentum of the electromagnetic wave is absorbed together with its energy. Consequently, the electron system can acquire a translational motion that is manifest in the form of a current or a voltage [...]”
Gibson and co-workers, who contributed much to the topic, focused on the transfer of linear momentum of photons to carriers in p-type germanium: upon absorption of the photon, an electron in a lower valence-band is promoted to an upper valence band, where there are holes thanks to the fact that the material is p-type. The electron gains energy and linear momentum. Though the momentum of light is small, the absorption of a large amount of photons leads to a measurable electric current or voltage. The effect is strong enough to use it for detection [5].
From a microscopic point of view, the linear photon-drag effect can be understood from Fig. 1. Transitions between two bands occur with the electron gaining a small amount of linear momentum k from the (plane wave) light field.
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| Figure 1: Linear photon-drag effect, Gibson model. |
A so-called "circular" photon-drag effect has been considered in the 80s. Here, the spin angular momentum of photons (or polarization of the field) is transferred to carriers, for example in quantum wells [6], and produce a photo-current that depends on the handness of circular polarization. [7]
Still another version of the effect is the generation of circular electric currents by the transfer of orbital angular momentum of light, studied for bulk [8, and also link] and nanostructured [9, and also link] semiconductors. In this case, twisted light induces interband transition between valence and conduction bands, producing circular electric currents.
References
[1] A.A. Grinberg, Theory of the Photoelectric and Photomagnetic Effects Produce by Light Pressure JETP, Vol. 31, No. 3, p. 531 1970. [found in http://www.jetp.ac.ru/cgi-bin/e/index/e/31/3/p531?a=list]
[2] Gibson, A. F., M F Kimmit, Walker, A. C., Photon drag in germanium, Applied Physics Letters 17 2 1970
[3] Gibson, A. F., Walker, A. C. (1971). Sign reversal of the photon drag effect in p type germanium. Journal of Physics C: Solid State Physics, 4(14), 2209.
[4] K Cameron, A F Gibson, J Giles, C B Hatch. M F Kimmit and S Shafik, The photon-drag spectrum of p-type germanium between 2.5 and 114 pm, J. Phys. C: Solid State Phys., Vol. 8, 1975.
[5] http://www.hamamatsu.com/eu/en/product/alpha/P/4147/index.html
[6] V. A. Shalygin H. Diehl Ch. HoffmannS. N. DanilovT. HerrleS. A. TarasenkoD. SchuhCh. GerlW. WegscheiderW. PrettlS. D. Ganichev, Spin Photocurrents and the Circular Photon Drag Effect in (110)-Grown Quantum Well Structures, JETP Letters January 2007, Volume 84, Issue 10, pp 570–576.
[7] Sergey D. Ganichev and Wilhelm Prettl, Spin Photocurrents in Quantum Wells review part I, https://arxiv.org/pdf/cond-mat/0304266.pdf
[8] G. F. Quinteiro, P. I. Tamborenea, Theory of the optical absorption of light carrying orbital angular momentum by semiconductors, EPL (Europhysics Letters) 85 (4), 47001
[9] G. F. Quinteiro, J. Berakdar, Electric currents induced by twisted light in quantum rings, Optics express 17 (22), 20465-20475
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