Zobrazeno 71 - 80
of 4 372
pro vyhledávání: '"Hirayama, Y."'
Publikováno v:
Revised version was published in Phys. Rev. B. 77, 155324 (2008).
We study effects of tilted magnetic fields on energy levels in a double-quantum-well (DQW) system, focusing on the coupling of subbands and Landau levels (LLs). The subband-LL coupling induces anticrossings between LLs, manifested directly in the mag
Externí odkaz:
http://arxiv.org/abs/0709.4306
Publikováno v:
Phys.Rev.B 77, 073310 (2008)
We present measurements of resonant tunneling through discrete energy levels of a silicon double quantum dot formed in a thin silicon-on-insulator layer. In the absence of piezoelectric phonon coupling, spontaneous phonon emission with deformation-po
Externí odkaz:
http://arxiv.org/abs/0707.3513
Publikováno v:
Phys. Rev. Lett. 99, 076805 (2007).
We investigate the electron spin states in the bilayer quantum Hall system at total Landau level filling factor nu =2 exploiting current-pumped and resistively detected NMR. The measured Knight shift, KS, of 75As nuclei reveals continuous variation o
Externí odkaz:
http://arxiv.org/abs/0707.1359
Publikováno v:
Appl. Phys. Lett. 90, 102118 (2007)
We study the nuclear spin population in a GaAs quantum well structure and demonstrate its initialization using an all-electrical nuclear magnetic resonance (NMR) device. In our device, nuclear spins are dynamically polarized in a sub-micron scale reg
Externí odkaz:
http://arxiv.org/abs/cond-mat/0702086
Publikováno v:
e-J. Surf. Sci. Nanotech 4, 669-673 (2006).
Coherent oscillations between any two levels from four nuclear spin states of I=3/2 have been demonstrated in a nanometre-scale NMR semiconductor device, where nuclear spins are all-electrically controlled. Using this device, we discuss quantum logic
Externí odkaz:
http://arxiv.org/abs/quant-ph/0612228
Autor:
Takashina, K., Brun, M., Ota, T., Maude, D. K., Fujiwara, A., Ono, Y., Takahashi, Y., Hirayama, Y.
We report anomalous structure in the magnetoresistance of SiO$_2$/Si(100)/SiO$_2$ quantum wells. When Landau levels of opposite valleys are driven through coincidence at the Fermi level, the longitudinal resistance displays elevations at filling fact
Externí odkaz:
http://arxiv.org/abs/cond-mat/0611662
Autor:
Klochan, O., Clarke, W. R., Danneau, R., Micolich, A. P., Ho, L. H., Hamilton, A. R., Muraki, K., Hirayama, Y.
We have fabricated and studied a ballistic one-dimensional p-type quantum wire using an undoped AlGaAs/GaAs heterostructure. The absence of modulation doping eliminates remote ionized impurity scattering and allows high mobilities to be achieved over
Externí odkaz:
http://arxiv.org/abs/cond-mat/0607509
Publikováno v:
J. Phys.: Condens. Matter 18 (2006) S885-S900
We have developed semiconductor point contact devices in which nuclear spins in a nanoscale region are coherently controlled by all-electrical methods. Different from the standard nuclear-magnetic resonance technique, the longitudinal magnetization o
Externí odkaz:
http://arxiv.org/abs/quant-ph/0605199
The valley splitting, which lifts the degeneracy of the lowest two valley states in a SiO$_2$/(100)Si/SiO$_2$ quantum well is examined through transport measurements. We demonstrate that the valley splitting can be observed directly as a step in the
Externí odkaz:
http://arxiv.org/abs/cond-mat/0604118
Autor:
Sasaki, S., Kang, S., Kitagawa, K., Yamaguchi, M., Miyashita, S., Maruyama, T., Tamura, H., Akazaki, T., Hirayama, Y., Takayanagi, H.
We have performed low-temperature transport measurements on a double quantum dot-quantum wire coupled device and demonstrated non-local control of the Kondo effect in one dot by manipulating the electronic spin states of the other. We discuss the mod
Externí odkaz:
http://arxiv.org/abs/cond-mat/0602373