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Related papers: Electron spin coherence in Si/SiGe quantum wells

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Direct electron spin resonance (ESR) on a high mobility two dimensional electron gas in a single AlAs quantum well reveals an electronic $g$-factor of 1.991 at 9.35 GHz and 1.989 at 34 GHz with a minimum linewidth of 7 Gauss. The ESR…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 M. Schulte , J. G. S. Lok , G. Denninger , W. Dietsche

Interactions of electron spins with rotational degrees of freedom during collisions or with external fields are fundamental processes that limit the coherence time of spin gases. We experimentally study the decoherence of hot cesium spins…

Quantum Physics · Physics 2025-05-29 Mark Dikopoltsev , Avraham Berrebi , Uriel Levy , Or Katz

We study the spin relaxation (SR) of a two-dimensional electron gas (2DEG) in the quantized Hall regime and discuss the role of spatial inhomogeneity effects on the relaxation. The results are obtained for small filling factors ($\nu\ll 1$)…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 S. Dickmann

Magnetotransport in 2DES's formed in Si-MOSFET's and Si/SiGe quantum wells at low temperatures is reported. Metallic temperature dependence of resistivity is observed for the n-Si/SiGe sample even in a parallel magnetic field of 9T, where…

Strongly Correlated Electrons · Physics 2009-10-31 Tohru Okamoto , K. Hosoya , S. Kawaji , A. Yagi , A. Yutani , Y. Shiraki

We imaged the transport of current-induced spin coherence in a two-dimensional electron gas confined in a triple quantum well. Nonlocal Kerr rotation measurements, based on the optical resonant amplification of the electrically-induced…

Mesoscale and Nanoscale Physics · Physics 2016-07-20 F. G. G. Hernandez , S. Ullah , G. J. Ferreira , N. M. Kawahala , G. M. Gusev , A. K. Bakarov

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

We have considered the conductivity properties of a two dimensional electron gas (2DEG) in two different kinds of inhomogeneous magnetic fields, i.e. a disordered distribution of magnetic flux vortices, and a periodic array of magnetic flux…

Condensed Matter · Physics 2009-10-22 Mads Nielsen , Per Hedegaard

The longitudinal spin relaxation time, T1, in a Si/SiGe quantum well is determined from the saturation of the ESR signal. We find values of a few microseconds. Investigations of T1 as a function of Fermi energy, concentration of scattering…

Soft Condensed Matter · Physics 2007-05-23 Z. Wilamowski , W. Jantsch

Long coherence times are key to the performance of quantum bits (qubits). Here, we experimentally and theoretically show that the Hahn-echo coherence time (T2) of electron spins associated with divacancy defects in 4H-SiC reaches 1.3 ms,…

Mesoscale and Nanoscale Physics · Physics 2016-10-03 Hosung Seo , Abram L. Falk , Paul V. Klimov , Kevin C. Miao , Giulia Galli , David D. Awschalom

Pure spin currents are measured in micron-wide channels of GaAs two-dimensional electron gas (2DEG). Spins are injected and detected using quantum point contacts, which become spin polarized at high magnetic field. High sensitivity to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 S. M. Frolov , A. Venkatesan , W. Yu , W. Wegscheider , J. A. Folk

Time-resolved Kerr rotation spectroscopy is used to monitor the room temperature electron spin dynamics of optical telecommunication wavelength AlInGaAs multiple quantum wells lattice-matched to InP. We found that electron spin coherence…

Mesoscale and Nanoscale Physics · Physics 2014-05-05 W. H. Lau , V. Sih , N. P. Stern , R. C. Myers , D. A. Buell , A. C. Gossard , D. D. Awschalom

The magnetic focusing of electrons has proven its utility in fundamental studies of electron transport. Here we report the direct imaging of magnetic focusing of electron waves, specifically in a two-dimensional electron gas (2DEG). We see…

Mesoscale and Nanoscale Physics · Physics 2007-08-08 K. E. Aidala , R. E. Parrott , T. Kramer , E. J. Heller , R. M. Westervelt , M. P. Hanson , A. C. Gossard

We investigate quantum coherence of electron spin transported through a semiconductor spintronic device, where spins are envisaged to be controlled by electrical means via spin-orbit interactions. To quantify the degree of spin coherence,…

Mesoscale and Nanoscale Physics · Physics 2017-08-23 Branislav K. Nikolic , Satofumi Souma

Here, we report an alternative route to achieve two dimensional electron gas (2DEG) in a semiconductor structure. It has been shown that charge accumulation on the side facets can lead to the formation of 2DEG in a network of c-axis…

Mesoscale and Nanoscale Physics · Physics 2014-10-07 H. P. Bhasker , Varun Thakur , S. M. Shivaprasad , S. Dhar

Erbium implanted silicon as a quantum technology platform has both telecommunications and integrated circuit processing compatibility. In Si implanted with Er to a concentration of 3x10^17 cm^3 and O to a concentration of 10^20 cm^3, the…

Utilizing time-resolved Kerr rotation techniques, we have investigated the spin dynamics of a high mobility, low density two dimensional electron gas in a GaAs/Al0:35Ga0:65As heterostructure in dependence on temperature from 1.5 K to 30 K.…

Other Condensed Matter · Physics 2009-11-13 X. Z. Ruan , H. H. Luo , Yang Ji , Z. Y. Xu , V. Umansky

We propose a method based on optically detected magnetic resonance (ODMR) to measure the decoherence time $T_{2}$ of a single electron spin in a semiconductor quantum dot. The electron spin resonance (ESR) of a single excess electron on a…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Oliver Gywat , Hans-Andreas Engel , Daniel Loss , R. J. Epstein , F. M. Mendoza , D. D. Awschalom

We report electrical conductivity $\sigma$ measurements on a range of two-dimensional electron gases (2DEGs) of varying linear extent. Intriguingly, at low temperatures ($T$) and low carrier density ($n_{\mathrm{s}}$) we find the behavior…

Mesoscale and Nanoscale Physics · Physics 2016-05-25 Dirk Backes , Richard Hall , Michael Pepper , Harvey Beere , David Ritchie , Vijay Narayan

We report on time-resolved Kerr rotation measurements of spin coherence of electrons in the first excited subband of a high-mobility low-density two-dimensional electron system in a GaAs/Al0.35Ga0.65As heterostructure. While the transverse…

Materials Science · Physics 2015-05-13 Haihui Luo , Xuan Qian , Xuezhong Ruan , Yang Ji

We have considered the conductivity properties of a two dimensional electron gas (2DEG) in two different kinds of inhomogeneous magnetic fields, i.e.\ a disordered distribution of magnetic flux vortices, and a periodic array of magnetic…

Condensed Matter · Physics 2016-08-14 Mads Nielsen , Per Hedegård