Optically rewritable patterns of nuclear magnetization in gallium arsenide.
The control of nuclear spin polarization is important to the design of materials and algorithms for spin-based quantum computing and spintronics. Towards that end, it would be convenient to control the sign and magnitude of nuclear polarization as a function of position within the host lattice. Here we show that, by exploiting different mechanisms for electron-nuclear interaction in the optical pumping process, we are able to control and image the sign of the nuclear polarization as a function of distance from an irradiated GaAs surface. This control is achieved using a crafted combination of light helicity, intensity and wavelength, and is further tuned via use of NMR pulse sequences. These results demonstrate all-optical creation of micron scale, rewritable patterns of positive and negative nuclear polarization in a bulk semiconductor without the need for ferromagnets, lithographic patterning techniques, or quantum-confined structures.
Department of Chemical Engineering, University of California, 201 Gilman Hall, Berkeley, California 94720, USA. jpking@berkeley.edu
Jonathan P
JP
King
Yunpu
Y
Li
Carlos A
CA
Meriles
Jeffrey A
JA
Reimer
D001152:Arsenicals / Q000737:chemistry*; D004583:Electrons; D005708:Gallium / Q000737:chemistry*; D055095:Optics and Photonics; D012666:Semiconductors
D001152:Arsenicals; C043055:gallium arsenide; D005708:Gallium