Gate voltage dependence of nuclear spin relaxation in an impurity-doped semiconductor quantum well

Observation of strains caused by heterostructure interfaces

“…Contrary to the case of RDNMR [2,3] and ODNMR [4] where the quadrupolar satellites are clearly split from the central line, no clear-cut splittings but only a broadened structure was observed. This is explained by the difference in the spatial distribution that the signals come from.…”

“…It may be tempting to argue that our strain value is roughly 10 times larger than those detected by RDNMR (14 kHz [2], 18 kHz [3] for both 69 Ga) but rather closer to the 90 kHz [4] [4] to 53 kHz. Thus, it is clarified that the apparent 190 kHz split frequency in our case indicates that the EFG probed by the Al nuclear spins is 54 times greater than the EFG detected by RDNMR.…”

“…Note that the 150 kHz split frequency for 75 As is greater than the value of 90 kHz from Ref. [4]. More importantly, we would like to stress that the 150 kHz splitting should be normalized to 88 kHz for 69 Ga, which is roughly 10 times smaller than the 69 Ganormalized splitting of 756 kHz for the mutli-quantum wells.…”

“…From the simulation of the spectrum, the quadrupolar splitting is found to be 190 kHz. Here we refer the quadrupolar split frequencies observed in RDNMR [2,3] and ODNMR [4].…”

“…More recently, RDNMR has been employed to observe strain in the breakdown regime of a quantum Hall state of a heterostructured GaAs [3]. In addition, the quadrupolar-split in a heterostructured sample is observed through optically detected NMR (ODNMR) [4]. In these methods, however, strains only on the interface can be detected.…”