Toward high-frequency operation of spin lasers

Abstract

Injecting spin-polarized carriers into semiconductor lasers provides important opportunities to extend what is known about spintronic devices, as well as to overcome many limitations of conventional (spin-unpolarized) lasers. By developing a microscopic model of spin-dependent optical gain derived from an accurate electronic structure in a quantum well-based laser, we study how its operation properties can be modified by spin-polarized carriers, carrier density, and resonant cavity design. We reveal that by applying an uniaxial strain it is possible to attain a large birefringence. While such birefringence is viewed as detrimental in conventional lasers, it could enable fast polarization oscillations of the emitted light in spin-lasers which can be exploited for optical communication and high-performance interconnects. The resulting oscillation frequency (> 200 GHz) would significantly exceed the frequency range possible in conventional lasers.

Giant Faraday Rotation in Metal-Fluoride Nanogranular Films

“…Optical isolators utilizing Faraday rotation are of importance in many applications, such as quality assurance of optical amplifiers 1 , optical ring lasers 2 , and optical communication systems 3–5 . They are highly reliable and important tools to support advanced information technology.…”

Spin relaxation in wurtzite nanowires

“…Exemplary in this context are optical orientation measurements or spin lasers, where the spin densities are homogeneously excited along the wire axis. 13,48,75 For this reason, we will pay special attention to this scenario in Sec. III B 2.…”

“…1 Aside from being the essential cornerstone for several fundamental discoveries, 2-5 they will constitute a key element in the realization of future electronic and spintronic devices. [6][7][8][9][10][11][12][13][14] To support this technical progress, a sound knowledge and reliable control of the system's transport parameters, the spin-orbit coupling (SOC), and the spin relaxation are essential.…”

Spin-orbit coupling effects and g-factors in zinc-blende InSb and wurtzite InAs nanowires using realistic multiband k · p method

“…The spin control (or spintronics) 9 in nanostructures is an example where a fundamental phenomenon is explored to implement unique devices in its functions, such as the integration of memory and logic using the spin quantum Hall effect 10,11 or using carbon nanotubes, 12 or the use of spin polarization to increase laser efficiency. [13][14][15] Recently, the field of spintronic got fueled again with the re-interpretation of the quantum spin Hall effect, 7 where the spin-orbit interaction generates surface spin-polarized currents going in opposite directions thus creating a transverse spin-polarized (helical) current even without a magnetic field. 16,17 Before the quantum spin Hall effect, the integer Hall effect was known to support topologically protected edge states.…”

“…Therefore, the spin control in lasers allows light with a high degree of polarization and low energy consumption and, by consequence, an efficient operation. 14,15 Experimentally, reliable determination of the spin-orbit coupling strength in nanowires is a challenging task. 60 Nevertheless, it has been investigated in a variety of distinct setups 61,62 each one leading to different values for the spin-orbit coupling strength.…”