中文
相关论文

相关论文: Light-Activated Nuclear Spin Polarization in Dilut…

200 篇论文

We study the mechanism of dynamical nuclear spin polarization by hyperfine interaction in spin-blocked double quantum dot system. We calculate the hyperfine transition rates and solve the master equations for the nuclear spins.…

介观与纳米尺度物理 · 物理学 2009-11-10 Changxue Deng , Xuedong Hu

We find that photoexcited electrons in an n-GaAs epilayer rapidly (< 50 ps) spin-polarize due to the proximity of an epitaxial ferromagnetic metal. Comparison between MnAs/GaAs and Fe/GaAs structures reveals that this coherent spin…

介观与纳米尺度物理 · 物理学 2009-11-07 R. J. Epstein , I. Malajovich , R. K. Kawakami , Y. Chye , M. Hanson , P. M. Petroff , A. C. Gossard , D. D. Awschalom

We probe the real space electronic response to a local magnetic impurity in isovalent and heterovalent doped BaFe2As2 (122) using Nuclear Magnetic Resonance (NMR). The local moments carried by Mn impurities doped into…

超导电性 · 物理学 2021-11-24 D. LeBoeuf , Y. Texier , M. Boselli , A. Forget , D. Colson , J. Bobroff

The lead halide perovskite nanocrystals embedded into a glass matrix exhibit strong interaction with light and demonstrate exceptional optical and spin related features along with long-term chemical and physical stability. We apply the spin…

介观与纳米尺度物理 · 物理学 2025-02-25 V. O. Kozlov , I. A. Smirnov , M. S. Kuznetsova , E. V. Kolobkova , G. G. Kozlov , V. S. Zapasskii , D. S. Smirnov , I. I. Ryzhov

We study the optically induced spin polarization, spin dephasing and diffusion in several high-mobility two-dimensional electron systems, which are embedded in GaAs quantum wells grown on (110)-oriented substrates. The experimental…

介观与纳米尺度物理 · 物理学 2015-06-17 R. Voelkl , M. Schwemmer , M. Griesbeck , S. A. Tarasenko , D. Schuh , W. Wegscheider , C. Schueller , T. Korn

We present a detailed study of the magnetic-field and temperature-dependent polarization of the near-band-gap photoluminescence in Gd-doped GaN layers. Our study reveals an extraordinarily strong influence of Gd doping on the electronic…

材料科学 · 物理学 2007-05-23 V. F. Sapega , M. Ramsteiner , S. Dhar , O. Brandt , K. H. Ploog

Among the possible types of magnetic dipole interactions in molecular systems, couplings between nuclear motion and the nuclear spin have probably received the least attention in molecular spectroscopy. Although very small in comparison to…

化学物理 · 物理学 2026-04-22 Matthias Diez , Johannes K. Krondorfer , Albert Hirtenfelder , Andreas W. Hauser

The exciton recombination and spin dynamics are investigated both experimentally and theoretically in an ensemble of indirect band gap (In,Al)As/AlAs quantum dots (QDs) with type-I band alignment. The magnetic-field-induced circular…

介观与纳米尺度物理 · 物理学 2025-07-08 T. S. Shamirzaev , D. R. Yakovlev , D. S. Smirnov , V. N. Mantsevich , D. Kudlacik , A. Yu. Gornov , A. K. Gutakovskii , M. Bayer

Positive signs of the effective g-factors for free electrons in the conduction band and electrons localized on deep paramagnetic centers have been measured in nitrogen dilute alloy GaAs{0.979}N{0.021} at room temperature. The g-factor signs…

介观与纳米尺度物理 · 物理学 2009-11-13 V. K. Kalevich , E. L. Ivchenko , A. Yu. Shiryaev , M. M. Afanasiev , A. Yu. Egorov , M. Ikezawa , Y. Masumoto

We report on the direct measurement of the electron spin splitting and the accompanying nuclear Overhauser (OH) field, and thus the underlying nuclear spin polarization (NSP) and fluctuation bandwidth, in a single InAs quantum dot under…

介观与纳米尺度物理 · 物理学 2021-01-04 Aaron M. Ross , Allan S. Bracker , Michael K. Yakes , Daniel Gammon , L. J. Sham , Duncan G. Steel

The polarizabilities $\alpha$ (electric), $\beta$ (magnetic) and $\gamma_\pi$ (backward spin) of the nucleon are investigated in terms of degrees of freedom of the nucleon using recent results for the CGLN amplitudes and resonance couplings…

高能物理 - 唯象学 · 物理学 2013-06-26 Martin Schumacher

We study the optical orientation of electron spins in GaAs/AlGaAs quantum wells for excitation in the growth direction and for in-plane excitation. Time- and polarization-resolved photoluminescence excitation measurements show, for resonant…

介观与纳米尺度物理 · 物理学 2012-11-19 S. Pfalz , R. Winkler , N. Ubbelohde , D. Hägele , M. Oestreich

GaAs/AlGaAs quantum dots grown by in-situ droplet etching and nanohole infilling offer a combination of strong charge confinement, optical efficiency, and spatial symmetry required for polarization entanglement and spin-photon interface.…

We propose an implementation for quantum information processing based on coherent manipulations of nuclear spins I=3/2 in GaAs semiconductors. We describe theoretically an NMR method which involves multiphoton transitions and which exploits…

介观与纳米尺度物理 · 物理学 2009-11-07 Michael N. Leuenberger , Daniel Loss , Martino Poggio , David D. Awschalom

We demonstrate the epitaxial growth of optical-quality electrically-gated III-V ferromagnetic quantum structures. Photoluminescence spectroscopy reveals that initially unpolarized photoexcited holes in a GaAs quantum well become…

材料科学 · 物理学 2007-05-23 R. C. Myers , A. C. Gossard , D. D. Awschalom

The properties of diluted Ga$_{1-x}$Mn$_x$As are calculated for a wide range of Mn concentrations within the local spin density approximation of density functional theory. M\"ulliken population analyses and orbital-resolved densities of…

介观与纳米尺度物理 · 物理学 2025-06-10 Stefano Sanvito , Pablo Ordejon , Nicola A. Hill

We demonstrate room-temperature spin-polarized ultrafast ($\sim$10 ps) lasing in a highly optically excited GaAs microcavity. This microcavity is embedded with InGaAs multiple quantum wells in which the spin relaxation time is less than 10…

介观与纳米尺度物理 · 物理学 2015-05-22 Feng-kuo Hsu , Wei Xie , Yi-Shan Lee , Sheng-Di Lin , Chih-Wei Lai

The effect of hyperfine interaction on the room-temperature defect-enabled spin filtering effect in GaNAs alloys is investigated both experimentally and theoretically through a master equation approach based on the hyperfine and Zeeman…

介观与纳米尺度物理 · 物理学 2015-06-17 C. Sandoval-Santana , A. Balocchi , T. Amand , J. C. Harmand , A. Kunold , X. Marie

Low thermal polarization of nuclear spins is a primary sensitivity limitation for nuclear magnetic resonance. Here we demonstrate optically pumped (microwave-free) nuclear spin polarization of $^{13}\mathrm{C}$ and $^{15}\mathrm{N}$ in…

介观与纳米尺度物理 · 物理学 2017-08-09 Ben L. Green , Ben G. Breeze , Gregory J. Rees , John V. Hanna , Jyh-Pin Chou , Viktor Ivády , Adam Gali , Mark E. Newton

We show that optical pumping of electron spins in individual InGaAs quantum dots leads to strong nuclear polarisation that we measure via the Overhauser shift (OHS) in magneto-photoluminescence experiments between 0 and 4T. We find a…

介观与纳米尺度物理 · 物理学 2009-11-11 P. -F. Braun , B. Urbaszek , T. Amand , X. Marie , O. Krebs , B. Eble , A. Lemaitre , P. Voisin