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Electric field enhanced electron spin coherence is characterized using time-resolved Faraday rotation spectroscopy in n-type ZnO epilayers grown by molecular beam epitaxy. An in-plane dc electric field E almost doubles the transverse spin…

Materials Science · Physics 2009-11-13 S. Ghosh , D. W. Steuerman , B. Maertz , K. Ohtani , Huaizhe Xu , H. Ohno , D. D. Awschalom

We investigate theoretically the coherent longitudinal and transversal spin relaxation of photoexcited electrons in quantum wells in quantized magnetic fields. We find the relaxation time for typical quantum well parameters between 100 and…

Disordered Systems and Neural Networks · Physics 2009-11-11 E. Ya. Sherman , J. E. Sipe

The temperature dependence of electron spin coherence in singly negatively charged (In,Ga)As/GaAs quantum dots is studied by time-resolved Faraday rotation. The decoherence time T2 is constant on a microsecond scale for temperatures below…

Materials Science · Physics 2008-07-14 F. G. G. Hernandez , A. Greilich , F. Brito , M. Wiemann , D. R. Yakovlev , D. Reuter , A. D. Wieck , M. Bayer

We show that the g-factor and the spin-flip time T_{1} of a heterojunction quantum dot is very sensitive to the band-bending interface electric field even in the absence of wave function penetration into the barrier. When this electric…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Rogerio de Sousa , S. Das Sarma

A dielectric vertical cavity is used to study the spin dynamics of molecularly self-assembled colloidal CdSe quantum dots (QDs). Using this structure, a nearly 30-fold enhancement of Faraday rotation is observed, which scales with the…

Materials Science · Physics 2007-05-23 D. W. Steuerman , Y. Q. Li , J. Berezovsky , D S. Seferos , G C. Bazan , D. D. Awschalom

The electron spin dynamics in multilayer GaAs/AlGaAs quantum wells, containing high-mobility dense two-dimensional electron gases, have been studied using time-resolved Kerr rotation and resonant spin amplification techniques. The electron…

Mesoscale and Nanoscale Physics · Physics 2018-08-15 S. Ullah , G. M. Gusev , A. K. Bakarov , F. G. G. Hernandez

The carrier spin coherence in a p-doped GaAs/(Al,Ga)As quantum well with a diluted hole gas has been studied by picosecond pump-probe Kerr rotation with an in-plane magnetic field. For resonant optical excitation of the positively charged…

Other Condensed Matter · Physics 2009-11-13 M. Syperek , D. R. Yakovlev , A. Greilich , J. Misiewicz , M. Bayer , D. Reuter , A. D. Wieck

Exciton, trion and electron spin dynamics in a 20 nm wide modulation-doped GaAs single quantum well are investigated using resonant ultrafast two-color Kerr rotation spectroscopy. Excitons and trions are selectively detected by resonant…

Mesoscale and Nanoscale Physics · Physics 2016-08-24 Sergiu Anghel , Akshay Singh , Felix Passmann , Hikaru Iwata , Nick Moore , Go Yusa , Xiaoqin Li , Markus Betz

We investigated the spin coherence of high-mobility two-dimensional electron gases confined in multilayer GaAs quantum wells. The dynamics of the spin polarization was optically studied using pump-probe techniques: time-resolved Kerr…

Mesoscale and Nanoscale Physics · Physics 2016-06-02 S. Ullah , G. M. Gusev , A. K. Bakarov , F. G. G. Hernandez

Time-resolved Faraday rotation is used to measure the coherent electron spin precession in a GaAs/InGaAs quantum well below an interdigitated magnetized Fe grating. We show that the electron spin precession frequency can be modified by…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 L. Meier , G. Salis , C. Ellenberger , E. Gini , K. Ensslin

A five-level {\Pp} model of the band structure for GaAs-type semiconductors is used to describe the spin $g^*$-factor and the cyclotron mass $m^*_c$ of conduction electrons in GaAs/Ga$_{1-x}$Al$_x$As quantum wells in an external magnetic…

Materials Science · Physics 2009-11-11 P. Pfeffer , W. Zawadzki

Electron spins in an InGaAs semiconductor quantum well are used as a magnetometer of magnetic stray-fields from patterned Fe stripes. Using time-resolved Faraday rotation, the coherent precession of quantum-well spins in the inhomogeneous…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 L. Meier , G. Salis , C. Ellenberger , E. Gini , K. Ensslin

We describe the growth of modulation-doped ZnSe/(Zn,Cd)Se quantum wells on (110) GaAs substrates. Unlike the well-known protocol for the epitaxy of ZnSe-based quantum structures on (001) GaAs, we find that the fabrication of quantum well…

The temperature dependence of the electron spin $g$ factor in GaAs is investigated experimentally and theoretically. Experimentally, the $g$ factor was measured using time-resolved Faraday rotation due to Larmor precession of electron spins…

Materials Science · Physics 2009-11-13 W. Zawadzki , P. Pfeffer , R. Bratschitsch , Z. Chen , S. T. Cundiff , B. N. Murdin , C. R. Pidgeon

We have measured T1 spin lifetimes of a 14 nm modulation-doped (100) GaAs quantum well using a time-resolved pump-probe Kerr rotation technique. The quantum well was selected by tuning the wavelength of the probe laser. T1 lifetimes in…

Mesoscale and Nanoscale Physics · Physics 2019-04-02 J. S. Colton , D. Meyer , K. Clark , D. Craft , J. Cutler , T. Park , P. White

We use time-resolved Kerr rotation to demonstrate the optical and electronic tuning of both the electronic and local moment (Mn) spin dynamics in electrically gated parabolic quantum wells derived from II-VI diluted magnetic semiconductors.…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 R. C. Myers , K. C. Ku , X. Li , N. Samarth , D. D. Awschalom

Time-resolved optical measurements of electron-spin dynamics in a (110) GaAs quantum well are used to study the consequences of a strongly anisotropic electron g-tensor, and the origin of previously discovered all-optical nuclear magnetic…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 G. Salis , D. D. Awschalom , Y. Ohno , H. Ohno

To establish a correlation between the spin diffusion, the spin lifetime, and the electron density, we study, employing time-resolved magneto-optical Kerr effect microscopy, the spin polarization evolution in low-dimensional GaAs…

Mesoscale and Nanoscale Physics · Physics 2022-08-17 S. Anghel , A. V. Poshakinskiy , K. Schiller , G. Yusa , T. Mano , T. Noda , M. Betz

A system of two quantum wells (QW), one made of HgCdTe and the other of HgCdMnTe, subjected to electric and magnetic fields $F$ and $B$ parallel to the growth direction, is proposed and described theoretically. It is shown that in such a…

Materials Science · Physics 2012-06-21 Pawel Pfeffer , Wlodek Zawadzki

We report on the experimental evidence for a nanosecond time-scale spin memory based on nonradiative excitons. The effect manifests itself in magnetic-field-induced oscillations of the energy of the optically active (radiative) excitons.…

Mesoscale and Nanoscale Physics · Physics 2019-04-17 A. V. Trifonov , E. S. Khramtsov , K. V. Kavokin , I. V. Ignatiev , A. V. Kavokin , Y. P. Efimov , S. A. Eliseev , P. Yu. Shapochkin , M. Bayer