Spin photocurrents in (110)-grown quantum well structures

Diehl, Helgi; Shalygin, V. A.; Belkov, Vassilij; Hoffmann, Christoph; Danilov, Sergey; Herrle, Thomas; Tarasenko, S. A.; Schuh, Dieter; Gerl, Christian; Wegscheider, Werner; Prettl, Wilhelm; Ganichev, Sergey

doi:10.1088/1367-2630/9/9/349

Cited by 41 publications

(47 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These measurements were particularly motivated by the search for the circular photogalvanic [14,68,69] and circular photon drag effects [70,71], i.e., photocurrents changing their direction upon switching of the radiation helicity [10,11,13], recently observed for Bi 2 Te 3 TI excited by near-infrared light [30]. Applying radiation at oblique incidence and measuring the photocurrent in the direction normal to the plane of incidence (yz), i.e., in the geometry for which circular photogalvanic [30,72,73] and circular photon drag effects [13,70] are expected, we detected a current which can be well fitted by J x = A x (f )(cos 4ϕ + 1)/2 (see Fig. 9).…”

Section: Resultsmentioning

confidence: 99%

Photon drag effect in(Bi1−xSbx)2Te3three-dimensional topological insulators

et al. 2016

View full text Add to dashboard Cite

We report on the observation of a terahertz radiation-induced photon drag effect in epitaxially grown nand p-type (Bi 1−x Sb x ) 2 Te 3 three-dimensional topological insulators with different antimony concentrations x varying from 0 to 1. We demonstrate that the excitation with polarized terahertz radiation results in a dc electric photocurrent. While at normal incidence a current arises due to the photogalvanic effect in the surface states, at oblique incidence it is outweighed by the trigonal photon drag effect. The developed microscopic model and theory show that the photon drag photocurrent can be generated in surface states. It arises due to the dynamical momentum alignment by time-and space-dependent radiation electric field and implies the radiation-induced asymmetric scattering in the electron momentum space. We show that the photon drag current may also be generated in the bulk. Both surface states and bulk photon drag currents behave identically upon variation of such macroscopic parameters as radiation polarization and photocurrent direction with respect to the radiation propagation. This fact complicates the assignment of the trigonal photon drag effect to a specific electronic system.

show abstract

Section: Resultsmentioning

confidence: 99%

Photon drag effect in(Bi1−xSbx)2Te3three-dimensional topological insulators

et al. 2016

View full text Add to dashboard Cite

show abstract

“…However, the SCA can make erroneous predictions if used outside the regime of its validity. To illustrate this point we present, in Section II, the predictions of semiclassical and fully quantum theories of a fundamental nonlinear response in metals with low symmetry -the photogalvanic effect (PGE) [14][15][16] . The term "photogalvanic" refers to the generation of a dc current by a time-varying electric field, with amplitude proportional to the square of the applied field.…”

Section: Introductionmentioning

confidence: 99%

Semiclassical theory of nonlinear magneto-optical responses with applications to topological Dirac/Weyl semimetals

et al. 2016

View full text Add to dashboard Cite

We study nonlinear magneto-optical responses of metals by a semiclassical Boltzmann equation approach. We derive general formulas for linear and second order nonlinear optical effects in the presence of magnetic fields that include both Berry curvature and orbital magnetic moment. Applied to Weyl fermions, the semiclassical approach (i) captures the directional anisotropy of linear conductivity under magnetic field as a consequence of an anisotropic B 2 contribution, which may explain the low-field regime of recent experiments; (ii) predicts strong second harmonic generation proportional to B that is enhanced as the Fermi energy approaches the Weyl point, leading to large nonlinear Kerr rotation. Moreover, we show that the semiclassical formula for the circular photogalvanic effect arising from the Berry curvature dipole is reproduced by a full quantum calculation using a Floquet approach.

show abstract

“…[22][23][24][25] These spin currents are generated optically, without applying any external electric fields. However, in each of these studies currents were detected not by optical techniques but by measuring steady-state voltage [16][17][18][19][20][21][22][23][24][25] caused only by the charge component of the currents. Therefore, not only has the degree of spin polarization of these photogenerated currents not measured but, strictly speaking, even the existence of a spin component of these currents has not been experimentally demonstrated since spin polarized carriers do not necessarily carry a spin polarized current.…”

mentioning

confidence: 99%

All-optical generation and detection of subpicosecond ac spin-current pulses in GaAs

et al. 2008

View full text Add to dashboard Cite

Subpicosecond ac spin-current pulses are generated optically in GaAs bulk and quantum wells at room temperature and at 90 K through quantum interference between one-photon and two-photon absorptions driven by two phase-locked ultrafast laser pulses that are both circularly polarized. The dynamics of the current pulses are detected optically by monitoring, in real time and in real space, the nanoscale motion of electrons with high-resolution pump probe techniques. The spin polarization of the currents is 0.6Ϯ 0.1, with peak current densities on the order of 10 2 A / m 2 .

show abstract

Spin photocurrents in (110)-grown quantum well structures

Cited by 41 publications

References 16 publications

Photon drag effect in(Bi1−xSbx)2Te3three-dimensional topological insulators

Photon drag effect in(Bi1−xSbx)2Te3three-dimensional topological insulators

Semiclassical theory of nonlinear magneto-optical responses with applications to topological Dirac/Weyl semimetals

All-optical generation and detection of subpicosecond ac spin-current pulses in GaAs

Contact Info

Product

Resources

About