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Related papers: Optical spin orientation and depolarization in Ge

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In this letter, we first show electrical spin injection in the germanium conduction band at room temperature and modulate the spin signal by applying a gate voltage to the channel. The corresponding signal modulation agrees well with the…

This article reviews spin-dependent transport of carriers in homogenous three-dimensional and two-dimensional semiconductors. We begin with a discussion of optical orientation of electron spins, which allows both the creation and detection…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 R. Winkler

In this work, we devise a fast and effective nuclear spin hyperpolarization scheme, which is in principle magnetic field and temperature independent. We use this scheme to experimentally demonstrate polarizations of up to 66% for phosphorus…

Electrically-induced electron spin polarization is imaged in n-type ZnSe epilayers using Kerr rotation spectroscopy. Despite no evidence for an electrically-induced internal magnetic field, current-induced in-plane spin polarization is…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 N. P. Stern , S. Ghosh , G. Xiang , M. Zhu , N. Samarth , D. D. Awschalom

We have measured the optical reflectivity $R(\omega)$ of $Eu_{0.6}Ca_{0.4}B_{6}$ as a function of temperature between 1.5 and 300 $K$ and in external magnetic fields up to 7 $T$. The slope at the onset of the plasma edge feature in…

Strongly Correlated Electrons · Physics 2009-11-10 A. Perucchi , G. Caimi , H. R. Ott , L. Degiorgi , A. D. Bianchi , Z. Fisk

We report the room-temperature electroluminescence (EL) with nearly pure circular polarization (CP) from GaAs-based spin-polarized light-emitting diodes (spin-LEDs). External magnetic fields are not used during device operation. There are…

Optics · Physics 2017-07-05 N. Nishizawa , K. Nishibayashi , H. Munekata

A long spin-lifetime of electrons is the holy grail of spintronics, a field exploiting the electron angular momentum as information carrier and storage unit. Previous reports indicated a spin lifetime, $\tau_{\text{s}}$ near $10$ ns at best…

Mesoscale and Nanoscale Physics · Physics 2026-02-04 Bence G. Márkus , Dávid Beke , Lili Vajtai , András Jánossy , László Forró , Ferenc Simon

By including the most recent observations of HI 21-cm absorption through near-by galactic disks, we confirm our previous assertion that there is an anti-correlation between the abundance of cool neutral atomic gas and impact parameter.…

Astrophysics of Galaxies · Physics 2020-04-01 S. J. Curran

A previous publication has shown that the in-plane polarization (IPP) component of a polarized 0.97-GeV/c deuteron beam in the COSY storage ring may acquire a polarization half-life in excess of 1000 s through a combination of beam…

Spin lasers leverage electron spin-polarisation to control photon polarisation, offering the potential for lower thresholds, rapid modulation, and all-optical data processing. We report successful spin injection into a commercial Vertical…

We study the origin of the step-like shoulder on the high energy side of the low temperature photoluminescence spectrum of heavily $p$-doped GaAs. We show experimentally that it is controlled by the Fermi-Dirac distribution of the holes and…

Mesoscale and Nanoscale Physics · Physics 2020-07-22 S. V. Poltavtsev , R. I. Dzhioev , V. L. Korenev , I. A. Akimov , D. R. Yakovlev , M. Bayer

The optical spin orientation effect in a GaAs/(Ga,Al)As quantum well containing a high-mobility 2D electron gas was found to be due to spin-polarized minority carriers, the holes. The observed oscillations of both the intensity and…

Mesoscale and Nanoscale Physics · Physics 2016-04-13 A. V. Koudinov , R. I. Dzhioev , V. L. Korenev , V. F. Sapega , Yu. G. Kusrayev

We report on time-resolved ultrafast optical spectroscopy study of the topological insulator (TI) Bi$_2$Se$_3$. We unravel that a net spin polarization can not only be generated using circularly polarized light via interband transitions…

Materials Science · Physics 2016-01-26 M. C. Wang , S. Qiao , Z. Jiang , S. N. Luo , J. Qi

The nature of the nano-scale environment presents a major challenge for solid-state implementation of spin-based qubits. In this work, a single electron spin in an optically pumped nanometer-sized III-V semiconductor quantum dot is used to…

The coherent spin dynamics of electrons and holes are studied in a FA0.9Cs0.1PbI2.8Br0.2 perovskite bulk crystal, using time-resolved Kerr ellipticity in a two-color pump-probe scheme. The probe photon energy is tuned to the exciton…

We report a photoluminescence study of high-quality Ge samples at temperatures 12 K $\leq$ T $\leq$ 295 K, over a spectral range that covers phonon-assisted emission from the indirect gap (between the lowest conduction band at the L point…

Materials Science · Physics 2020-05-28 José Menéndez , Christian D. Poweleit , Sean E. Tilton

We report on a picosecond-fast optical removal of spin polarization from a self-confined photo-carrier system at an undoped GaAs/AlGaAs interface possessing superior long-range and high-speed spin transport properties. We employed a…

Other Condensed Matter · Physics 2017-10-04 L. Nádvorník , M. Surýnek , K. Olejník , V. Novák , J. Wunderlich , F. Trojánek , T. Jungwirth , P. Němec

A spin-dependent emission of optically oriented electrons from p-GaAs(Cs,O) into vacuum was experimentally observed in a magnetic field normal to the surface. This phenomenon is explained within the model which takes into account the jump…

Mesoscale and Nanoscale Physics · Physics 2008-05-24 D. A. Orlov , V. L. Alperovich , A. S. Terekhov

We present experimental results of transverse electron-focusing measurements performed using n-type GaAs. In the presence of a small transverse magnetic field (B), electrons are focused from the injector to detector leading to focusing…

Mesoscale and Nanoscale Physics · Physics 2017-09-25 Chengyu Yan , Sanjeev Kumar , Michael Pepper , Patrick See , Ian Farrer , David Ritchie , Jonathan Griffiths , Geraint Jones

Germanium (Ge) has emerged as a contender for scalable solid-state spin qubits. This interest stems from the numerous attractive properties of hole spin in Ge low-dimensional systems and their compatibility with the standards of silicon…

Mesoscale and Nanoscale Physics · Physics 2025-02-26 Nicolas Rotaru , Patrick Del Vecchio , Oussama Moutanabbir