Sub-millisecond dynamic nuclear spin hyperpolarization in a semiconductor: A case study from PInantisite in InP

Nuclear polarization by optical pumping in InP:Fe above liquid nitrogen temperature

“…Presumably, the dominant reason for the small S z in our experiment is a large / l s τ τ , i.e., a spin relaxation time much shorter than the life time.The importance of the ratio τ l /τ s on DNP was recently demonstrated in InP by ODMR (optically detected magnetic resonance) [26]. By varying the life time of localized electrons via controlling the laser power, the authors showed that the nuclear hyperpolarization becomes larger as the lifetime becomes shorter than the spin relaxation time, which points to the necessity of controlling the lifetime and relaxation time to achieve higher enhancement.…”

Effect of hyperfine-induced spin mixing on the defect-enabled spin blockade and spin filtering in GaNAs

“…[10][11][12][13][14] HFI has been shown to be of paramount importance in a large variety of semiconductor systems that are promising for future spintronics and spin-based quantum computation. Examples include its vital role in the spin blockade in semiconductor double quantum dots (QDs) due to the mixing of singlet/triplet states, 10,11 in the magnetoresistance effect observed in organic semiconductors, 15 in spin decoherence/relaxation in InAs QDs, 16 in hyperpolarization of local nuclear spins in semiconductors, 17 and in controlling electron spin coherence time of the P donor site in Si 6 and the nitrogen-vacancy center in diamond in the vicinity of 13 C nuclei spin bath. 7 In this work, we attempt to examine the role of HFI in the room-temperature (RT) defect-engineered spin-filtering effect, which has recently been demonstrated to be able to generate >40% spin polarization (P e ) of free electrons [18][19][20][21][22][23][24][25][26][27][28] and to amplify fast-modulating spin signals up to 2700% at RT 29 in Ga(In)NAs alloys.…”