Spin relaxation in spin light-emitting diodes: effects of magnetic field and temperature

Henning Höpfner; Carola Fritsche; Arne Ludwig; Astrid Ludwig; Frank Stromberg; Heiko Wende; Werner Keune; Dirk Reuter; Andreas D. Wieck; Nils C. Gerhardt; Martin R. Hofmann

doi:10.1117/12.2001511

14 March 2013 Spin relaxation in spin light-emitting diodes: effects of magnetic field and temperature

Henning Höpfner, Carola Fritsche, Arne Ludwig, Astrid Ludwig, Frank Stromberg, Heiko Wende, Werner Keune, Dirk Reuter, Andreas D. Wieck, Nils C. Gerhardt, Martin R. Hofmann

Author Affiliations +

Proceedings Volume 8623, Ultrafast Phenomena and Nanophotonics XVII; 86230A (2013) https://doi.org/10.1117/12.2001511
Event: SPIE OPTO, 2013, San Francisco, California, United States

Abstract

We report experimental results on the electron spin relaxation length during vertical transport in spin lightemitting diodes (LEDs). Our devices are GaAs based LEDs with InAs quantum dots in the active region, an MgO tunnel barrier and an Fe/Tb multilayer spin injector with perpendicular magnetic anisotropy, i.e. remanent out-of-plane magnetization, enabling efficient electrical spin injection in magnetic remanence. Additionally, our devices can be operated at room temperature. A series of samples with different injection path lengths allows us to experimentally determine the spin relaxation length in our devices. In combination with operation in magnetic remanence, we are able to determine the spin relaxation length without the influence of external magnetic fields and at room temperature and find it to be 27 nm. Applying an additional external magnetic field, we find that at a field strength of 2 T, this relaxation length almost doubles, which is in good agreement with spin relaxation times in GaAs. Temperature control of our samples allows us to measure the temperature dependence of the spin relaxation length. At 200 K, the spin relaxation length doubles to 50 nm and reaches 80 nm at 30 K, in good agreement with theoretic calculations. Our results show that polarization values obtained with spin-LEDs inside strong magnetic fields and at low temperatures are not comparable to those in remanence and at room temperature. However, the transfer of efficient spintronic devices to such applicationenabling settings is absolutely necessary and will be a major challenge considering the enormous differences in spin relaxation.

Citation Download Citation

Henning Höpfner, Carola Fritsche, Arne Ludwig, Astrid Ludwig, Frank Stromberg, Heiko Wende, Werner Keune, Dirk Reuter, Andreas D. Wieck, Nils C. Gerhardt, and Martin R. Hofmann "Spin relaxation in spin light-emitting diodes: effects of magnetic field and temperature", Proc. SPIE 8623, Ultrafast Phenomena and Nanophotonics XVII, 86230A (14 March 2013); https://doi.org/10.1117/12.2001511

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
7 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Magnetism

Light emitting diodes

Polarization

Gallium arsenide

Spintronics

Spin polarization

Electroluminescence

Show All Keywords

Keywords/Phrases

Search In:

Publication Years