Magnetic-induced PL modulation of InGaN/GaN MQWs by a CoFeB ferromagnetic cap layer

III-nitride semiconductors show wide applications in general illumination, displays, visible-light communication, power electronics and so on. Until recently, it has been rather hard to experimentally realize magnetic modulation or coupling due to the lack of magnetism in GaN-based semiconductors. Here, we have fabricated the nonpolar a-plane InGaN/GaN MQWs capped by ferromagnetic CoFeB thin film. After magnetizing a CoFeB cap layer under a low magnetic field of 100 mT, the peak PL wavelength of nonpolar a-plane InGaN/GaN MQWs has a red shift from 460 to 475 nm, while its PL polarization degree shows an effective enhancement from 29% to 41% by increasing the CoFeB thickness. The magnetic-induced carrier redistribution has played a great role on the PL modulation of nonpolar InGaN/GaN MQW active region. Therefore, our proposed method exhibits a great potential to develop the highly polarized light emitters, optical polarization modulation, polarization-sensitive detectors, magnetic-optical modulation and coupling sensing in future multi-field applications. (C) 2019 The Japan Society of Applied Physics