Picture of mobile phone running fintech app

Fintech: Open Access research exploring new frontiers in financial technology

Strathprints makes available Open Access scholarly outputs by the Department of Accounting & Finance at Strathclyde. Particular research specialisms include financial risk management and investment strategies.

The Department also hosts the Centre for Financial Regulation and Innovation (CeFRI), demonstrating research expertise in fintech and capital markets. It also aims to provide a strategic link between academia, policy-makers, regulators and other financial industry participants.

Explore all Strathclyde Open Access research...

Spin induced gigahertz polarization oscillations in vertical-cavity surface-emitting laser devices

Ackemann, Thorsten and Li, M. Y. and Jaehme, H. and Soldat, H. and Gerhardt, N.C. and Hofmann, M. R. (2011) Spin induced gigahertz polarization oscillations in vertical-cavity surface-emitting laser devices. In: Vertical-Cavity Surface-Emitting Lasers XV. Proc. SPIE, 7952 . UNSPECIFIED, 79520B.

[img]
Preview
PDF
Li_ProcSpie_7952_79520B_2011_spinosc.pdf
Accepted Author Manuscript

Download (624kB) | Preview

Abstract

Spin-controlled vertical-cavity surface-emitting lasers (VCSELs) have been intensively studied in recent years because of the low threshold feasibility and the nonlinearity above threshold, which make spin-VCSELs very promising for spintronic devices. Here we investigate the circular polarization dynamics of VCSELs on a picosecond time scale after pulsed optical spin injection at room temperature. A hybrid excitation technique combining continuous-wave (cw) unpolarized electrical excitation slightly above threshold and pulsed polarized optical excitation is applied. The experimental results demonstrate ultrafast circular polarization oscillations with a frequency of about 11 GHz. The oscillations last inside the first undulation of the intensity relaxation oscillations. Via theoretical calculations based on a rate equation model we analyze these oscillations as well as the underlying physical mechanisms.