English
Related papers

Related papers: Exchange interaction-driven dynamic nuclear polari…

200 papers

Dynamic nuclear polarization transfers spin polarization from electrons to nuclei. We have achieved this by a new method, simultaneously exciting transitions of electronic and nuclear spins. The efficiency of this technique improves with…

Quantum Physics · Physics 2008-09-11 G. W. Morley , K. Porfyrakis , A. Ardavan , J. van Tol

In this paper we show that it is possible to switch the spin polarization of the photocurrent signal obtained from a single self-assembled quantum dot photodiode under the effect of elliptically polarized light by just increasing the light…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 J. M. Villas-Boas , Sergio E. Ulloa , A. O. Govorov

Conduction electrons are used to optically polarize, detect and manipulate nuclear spin in a (110) GaAs quantum well. Using optical Larmor magnetometry, we find that nuclear spin can be polarized along or against the applied magnetic field,…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 G. Salis , D. T. Fuchs , J. M. Kikkawa , D. D. Awschalom , Y. Ohno , H. Ohno

We demonstrate a new method for electrical manipulation of nuclear spins utilizing dynamic nuclear polarization induced by quantum Hall effect breakdown. Nuclear spins are polarized and detected through the hyperfine interaction between a…

Mesoscale and Nanoscale Physics · Physics 2009-04-17 Minoru Kawamura , Hiroyuki Takahashi , Yoshiaki Hashimoto , Shingo Katsumoto , Tomoki Machida

It is shown that in organic semiconductors where organic magnetoresistance (OMAR) is observed, the exchange interaction between electrons and holes localized at different molecules leads to dynamic spin polarization in the direction of the…

Disordered Systems and Neural Networks · Physics 2022-04-06 A. V. Shumilin

We report achieving enhanced nuclear magnetization in a magnetic resonance force microscope experiment at 0.6 tesla and 4.2 kelvin using the dynamic nuclear polarization (DNP) effect. In our experiments a microwire coplanar waveguide…

Hyperfine coupling of electron spins to nuclear spins is studied for a GaAs-based double quantum dot in the spin blockade regime where the electron conduction is mostly blocked by Pauli effect unless the electron spin state in the double…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Keiji Ono , Seigo Tarucha

Computational studies based on 6 band k$\cdot$p theory are employed on lens-shaped III-nitride quantum dots (QDs) with focus on the polarization properties of the optical interband transitions. The results predict pronounced linear…

Mesoscale and Nanoscale Physics · Physics 2013-11-25 Supaluck Amloy , K. Fredrik Karlsson , P. O Holtz

Understanding and manipulating spin polarization and transport in the vicinity of semiconductor-hosted defects is a problem of present technological and fundamental importance. Here, we use high-field magnetic resonance to monitor the…

Mesoscale and Nanoscale Physics · Physics 2014-01-14 Yunpu Li , Jonathan P. King , Jeffrey A. Reimer , Carlos A. Meriles

The dynamic polarization of nuclear spins interacting with resident electrons under resonant excitation of trions is studied in a nominally undoped GaAs/(Al,Ga)As quantum well. Unlike in common time-resolved pump-probe techniques, we used a…

Mesoscale and Nanoscale Physics · Physics 2018-11-28 M. Kotur , F. Saeed , R. W. Mocek , V. L. Korenev , I. A. Akimov , A. S. Bhatti , D. R. Yakovlev , D. Suter , M. Bayer

We analyze electron spin relaxation in electronic transport through coherently coupled double quantum dots in the spin blockade regime. In particular, we focus on hyperfine interaction as the spin relaxation mechanism. We pay special…

Mesoscale and Nanoscale Physics · Physics 2015-03-13 Carlos López-Monís , Jesús Iñarrea , Gloria Platero

A new method for local dynamic nuclear polarization is demonstrated in a GaAs/AlGaAs heterostructure at the Landau level filling factor $\nu=3$. Using a narrow channel sample, where the width varies stepwise along the electron flow, we find…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Yosuke Komori , Tohru Okamoto

We discuss the polarization dynamics during solid effect dynamic nuclear polarization (DNP) in a central spin model that consists of an electron surrounded by many nuclei. To this end we use a recently developed formalism and validate first…

Other Condensed Matter · Physics 2016-03-23 Daniel Wiśniewski , Alexander Karabanov , Igor Lesanovsky , Walter Köckenberger

We demonstrate that efficient optical pumping of nuclear spins in semiconductor quantum dots (QDs) can be achieved by resonant pumping of optically "forbidden" transitions. This process corresponds to one-to-one conversion of a photon…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 E. A. Chekhovich , M. N. Makhonin , K. V. Kavokin , A. B. Krysa , M. S. Skolnick , A. I. Tartakovskii

Hanle effect is ubiquitous in the study of spin-related phenomena and has been used to determine spin lifetime, precession and transport in semiconductors. Here, we report an experimental observation of anomalous Hanle effect in individual…

Mesoscale and Nanoscale Physics · Physics 2009-10-12 O. Krebs , P. Maletinsky , T. Amand , B. Urbaszek , A. Lemaître , P. Voisin , X. Marie , A. Imamoglu

The optical spectroscopy of a single InAs quantum dot doped with a single Mn atom is studied using a model Hamiltonian that includes the exchange interactions between the spins of the quantum dot electron-hole pair, the Mn atom and the…

Mesoscale and Nanoscale Physics · Physics 2008-12-24 J. van Bree , P. Koenraad , J. Fernandez-Rossier

An electron confined in a quantum dot interacts with its local nuclear spin environment through the hyperfine contact interaction. This interaction combined with external control and relaxation or measurement of the electron spin allows for…

Mesoscale and Nanoscale Physics · Physics 2014-04-08 Sophia E. Economou , Edwin Barnes

We studied spatial distribution of dynamic nuclear polarization (DNP) in a Hall-bar device in a breakdown regime of the quantum Hall effect (QHE). We detected nuclear magnetic resonance (NMR) signals from the polarized nuclear spins by…

Mesoscale and Nanoscale Physics · Physics 2011-01-25 Minoru Kawamura , Kimitoshi Kono , Yoshiaki Hashimoto , Shingo Katsumoto , Tomoki Machida

Dynamic nuclear polarization (DNP) is used in nuclear magnetic resonance (NMR) to transfer polarization from electron spins to nuclear spins. The resulting nuclear polarization enhancement can, in theory, be two or three orders of magnitude…

Quantum Physics · Physics 2015-10-14 Sarah Sheldon , David G. Cory

We report on efficient spin injection in p-doped InGaAs/GaAs quantum-dot (QD) spin light emitting diode (spin-LED) under zero applied magnetic field. A high degree of electroluminescence circular polarization (Pc) ~19% is measured in…