Tunability of electron spin coherence in III–V quantum wells

We have calculated both $T_1$ and $T_2$ for (110)-oriented GaAs/AlGaAs quantum wells near room temperature. The altered symmetry of (110)-oriented quantum wells leads to an increase in calculated spin coherence times ${\mathrm{(T}}_1)$ compared to those of similar (100)-oriented quantum wells, exceeding 1 ns at room temperature. We have also studied the electron spin coherence times as a function of applied electric field in (100)- and (110)-oriented GaAs/AlGaAs quantum wells. $T_1$ is considerably more responsive to the growth-direction electric field in (110)-oriented quantum wells than in (100)-oriented quantum wells, whereas the response of $T_2$ is similar for both growth directions.